JsonToProto returns empty payload

jsonToProto functions seems to return proto object but when sent as request object to the fullfilment it returns empty payload.

const payload = {
data: {
SmsSid: "SM1eb889baa86d1887d14c6007a6c5684a",
Body: "Hola",
SmsStatus: "received",
MessageSid: "SM1eb889baa86d1887d14c6007a6c5684a",
ApiVersion: "2010-04-01",
From: "whatsapp:+5218717953912",
AccountSid: "ACf71ea17bda8928547c7f0fa3f13d384b",
NumMedia: "0",
To: "whatsapp:+14155238886",
SmsMessageSid: "SM1eb889baa86d1887d14c6007a6c5684a",
NumSegments: "1"
}
};

const request = {
session: sessionPath,
queryInput: {
text: {
text: "Hola",
languageCode: LANGUAGE_CODE
}
},
queryParams: {
payload: this.jsonValueToProto(payload)
}
};