How to intigrate JOIN API with Zapier?

Ladies and Gentlemen,
We want to connect the JOIN API for the individual applications with Zapier. Here we use the code block and the python language.
Unfortunately, we already get an error code 422 in the mask (https://docs.join.com/reference/createapplication) and cannot test this with Zapier.
Please help us to get the individual applications from JOIN through Zapier, otherwise we will not be able to use the software.

Many thanks in advance