Use API to send Facebook message in Thunkable

I am currently making an app that can integrate facebook messages specifically send and receive facebook messages using Web API Component, I found that to send a message you have to submit a post request to the API with your page access token appended to the URL query string<your-accesstoken>
but the body of the HTTP request is sent in JSON format, so I convert this JSON
to a block that thunkable can read and ended up making these blocks

I’ve tried testing it but I get an error message (#100) The parameter recipient is required, I am very confuse at this point, what should I do? is there another way to send and receive facebook message?

Use this component