Jason.Encoder not implemented for module

I configure jason in my existing application by removing the poison. But some tests are failing The error is

   ** (Protocol.UndefinedError) protocol Jason.Encoder not implemented for %User{}.Jason.Encoder 
       protocol  must always be explicitly implemented.

I don’t have jason for this model . I don’t know why its throwing an error. if i remove the user struct from the view. then its giving me error about some other model which i don’t have jason encoder for.

Any suggestions?

Can you post the failing test here?

Any suggestions?

Maybe add jason encoder implementations for your structs.