I have my own gp service that gets a point as parameter.
After I published it I can run it from Pro, I can add it and run t from a WebMap and I can build a Web AppBuilder (old) that running it with no problem.
When I try to build experience builder and run it (Enterprise 11.5) I get the error you can see in the attachment.
Tring to run it with EB developer works fine!!
Is it a bug??