diff --git a/const.go b/const.go
index 6e78f96..45ef0ee 100644
--- a/const.go
+++ b/const.go
@@ -1,16 +1,16 @@
 package telegram
 
 // Version represents current version of Telegram API supported by this package
-const Version string = "5.1.0"
+const Version string = "5.2.0"
 
 // Action represents available and supported status actions of bot
 const (
 	ActionFindLocation    string = "find_location"
-	ActionRecordAudio     string = "record_audio"
+	ActionRecordVoice     string = "record_voice"
 	ActionRecordVideo     string = "record_video"
 	ActionRecordVideoNote string = "record_video_note"
 	ActionTyping          string = "typing"
-	ActionUploadAudio     string = "upload_audio"
+	ActionUploadVoice     string = "upload_voice"
 	ActionUploadDocument  string = "upload_document"
 	ActionUploadPhoto     string = "upload_photo"
 	ActionUploadVideo     string = "upload_video"
diff --git a/inline.go b/inline.go
index 56ab45f..37f1eea 100644
--- a/inline.go
+++ b/inline.go
@@ -16,6 +16,12 @@ type (
 		// Sender
 		From *User `json:"from"`
 
+		// Type of the chat, from which the inline query was sent. Can be either “sender” for a private chat
+		// with the inline query sender, “private”, “group”, “supergroup”, or “channel”. The chat type should
+		// be always known for requests sent from official clients and most third-party clients, unless the
+		// request was sent from a secret chat
+		ChatType string `json:"chat_type,omitempty"`
+
 		// Sender location, only for bots that request user location
 		Location *Location `json:"location,omitempty"`
 	}
@@ -882,6 +888,78 @@ type (
 		VCard string `json:"vcard,omitempty"`
 	}
 
+	// InputInvoiceMessageContent represents the content of an invoice message to be sent as the result of an inline query.
+	InputInvoiceMessageContent struct {
+		// Product name, 1-32 characters
+		Title string `json:"title"`
+
+		// Product description, 1-255 characters
+		Description string `json:"description"`
+
+		// Bot-defined invoice payload, 1-128 bytes. This will not be displayed to the user, use for your
+		// internal processes.
+		Payload string `json:"payload"`
+
+		// Payment provider token, obtained via Botfather
+		ProviderToken string `json:"provider_token"`
+
+		// Three-letter ISO 4217 currency code
+		Currency string `json:"currency"`
+
+		// Price breakdown, a JSON-serialized list of components (e.g. product price, tax, discount, delivery
+		// cost, delivery tax, bonus, etc.)
+		Prices []*LabeledPrice `json:"prices,omitempty"`
+
+		// The maximum accepted amount for tips in the smallest units of the currency (integer, not
+		// float/double). For example, for a maximum tip of US$ 1.45 pass max_tip_amount = 145. See the exp
+		// parameter in currencies.json, it shows the number of digits past the decimal point for each currency
+		// (2 for the majority of currencies). Defaults to 0
+		MaxTipAmount int `json:"max_tip_amount,omitempty"`
+
+		// A JSON-serialized array of suggested amounts of tip in the smallest units of the currency (integer,
+		// not float/double). At most 4 suggested tip amounts can be specified. The suggested tip amounts must
+		// be positive, passed in a strictly increased order and must not exceed max_tip_amount.
+		SuggestedTipAmounts []int `json:"suggested_tip_amounts,omitempty"`
+
+		// A JSON-serialized object for data about the invoice, which will be shared with the payment provider.
+		// A detailed description of the required fields should be provided by the payment provider.
+		ProviderData string `json:"provider_data,omitempty"`
+
+		// URL of the product photo for the invoice. Can be a photo of the goods or a marketing image for a
+		// service. People like it better when they see what they are paying for.
+		PhotoURL string `json:"photo_url,omitempty"`
+
+		// Photo size
+		PhotoSize int `json:"photo_size,omitempty"`
+
+		// Photo width
+		PhotoWidth int `json:"photo_width,omitempty"`
+
+		// Photo height
+		PhotoHeight int `json:"photo_height,omitempty"`
+
+		// Pass True, if you require the user's full name to complete the order
+		NeedName bool `json:"need_name,omitempty"`
+
+		// Pass True, if you require the user's phone number to complete the order
+		NeedPhoneNumber bool `json:"need_phone_number,omitempty"`
+
+		// Pass True, if you require the user's email address to complete the order
+		NeedEmail bool `json:"need_email,omitempty"`
+
+		// Pass True, if you require the user's shipping address to complete the order
+		NeedShippingAddress bool `json:"need_shipping_address,omitempty"`
+
+		// Pass True, if user's phone number should be sent to provider
+		SendPhoneNumberToProvider bool `json:"send_phone_number_to_provider,omitempty"`
+
+		// Pass True, if user's email address should be sent to provider
+		SendEmailToProvider bool `json:"send_email_to_provider,omitempty"`
+
+		// Pass True, if the final price depends on the shipping method
+		IsFlexible bool `json:"is_flexible,omitempty"`
+	}
+
 	// ChosenInlineResult represents a result of an inline query that was chosen by the user and sent to their
 	// chat partner.
 	ChosenInlineResult struct {
diff --git a/methods.go b/methods.go
index 11e22cc..4372af6 100644
--- a/methods.go
+++ b/methods.go
@@ -587,7 +587,7 @@ type (
 		ReplyMarkup ReplyMarkup `json:"reply_markup,omitempty"`
 	}
 
-	// SendChatAction represents data for SendChat method.
+	// SendChatAction represents data for SendChatAction method.
 	SendChatAction struct {
 		ChatID ChatID `json:"chat_id"`
 
diff --git a/payments.go b/payments.go
index 00b8c64..71feb7d 100644
--- a/payments.go
+++ b/payments.go
@@ -158,7 +158,7 @@ type (
 		ProviderToken string `json:"provider_token"`
 
 		// Unique deep-linking parameter that can be used to generate this invoice when used as a start parameter
-		StartParameter string `json:"start_parameter"`
+		StartParameter string `json:"start_parameter,omitempty"`
 
 		// Three-letter ISO 4217 currency code, see more on currencies
 		Currency string `json:"currency"`
@@ -172,6 +172,15 @@ type (
 		// Price breakdown, a list of components (e.g. product price, tax, discount, delivery cost, delivery tax, bonus, etc.)
 		Prices []*LabeledPrice `json:"prices"`
 
+		// The maximum accepted amount for tips in the smallest units of the currency (integer, not
+		// float/double). For example, for a maximum tip of US$ 1.45 pass max_tip_amount = 145. See the exp
+		// parameter in currencies.json, it shows the number of digits past the decimal point for each currency
+		// (2 for the majority of currencies). Defaults to 0
+		MaxTipAmount int `json:"max_tip_amount,omitempty"`
+
+		// A JSON-serialized array of suggested amounts of tips in the smallest units of the currency (integer, not float/double). At most 4 suggested tip amounts can be specified. The suggested tip amounts must be positive, passed in a strictly increased order and must not exceed max_tip_amount.
+		SuggestedTipAmounts []int `json:"suggested_tip_amounts,omitempty"`
+
 		// Photo size
 		PhotoSize int `json:"photo_size,omitempty"`
 
diff --git a/types.go b/types.go
index 8f7b52c..d081d56 100644
--- a/types.go
+++ b/types.go
@@ -263,6 +263,9 @@ type (
 		// Location.
 		ProximityAlertTriggered *ProximityAlertTriggered `json:"proximity_alert_triggered,omitempty"`
 
+		// Service message: voice chat scheduled
+		VoiceChatScheduled *VoiceChatScheduled `json:"voice_chat_scheduled,omitempty"`
+
 		// Service message: voice chat started
 		VoiceChatStarted *VoiceChatStarted `json:"voice_chat_started,omitempty"`
 
@@ -630,6 +633,12 @@ type (
 		MessageAutoDeleteTime int `json:"message_auto_delete_time"`
 	}
 
+	// VoiceChatScheduled represents a service message about a voice chat scheduled in the chat.
+	VoiceChatScheduled struct {
+		// Point in time (Unix timestamp) when the voice chat is supposed to be started by a chat administrator
+		StartDate int64 `json:"start_date"`
+	}
+
 	// VoiceChatStarted represents a service message about a voice chat started in the chat. Currently holds no
 	// information.
 	VoiceChatStarted struct{}