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Twilio inbound calls and texts webhooks

to anyone who is trying to setup a call system in your Bubble app where you respond to inbound calls and texts that you receive via webhook, you may encounter the following challenge with Twilio

Error - 12300 which means invalid content type. To solve this problem and remove the error, you need to add an api response workflow to the Api workflow / endpoint that is recieving the call as follows

Basically you need to give Twilio some instructions using their language called “Twiml” you can find the Twiml language reference here:

In this case we are saying Hello World! to the person calling in, you can add different Twiml to match your specific use case

Hope this helps anyone who is stuck on this in the future! It’s a simple fix but took me too long to figure out


Evan :slight_smile:


This is so awesome, thank you thank you thank you :heart: :heart: :heart: :heart:

I was running into this xml response error when trying to use webhooks with codeReadr. (service to scan barcodes). It works now :slight_smile: