Web API Error

Hi, I am trying to use a Web API to write to my database table but what I want to do is get the record from a public Web API and use that record in my Web API that writes to my table.

If I do it this way it works fine.

But if I use an expression rule it throws me a status 500 error.

Could you help me to understand please, I appreciate it.

  Discussion posts and replies are publicly visible