Hi Tony,
Based on the information you provided, all I could guess, the issue is with the data Type.
Please check the parameter type in the REST configuration you created and also make sure when calling keep the same data type.
Hope you resolve the issue!
Regards,
Ashok
From where are you calling this service? Probably the source is sending the connectionId as empty.
Also you can test it via Postman.
It appears you are correct on this Robert. I changed the parameter in the URL to confirm and it worked. However, this GET request cannot be changed. It will come through as ConnectionID from the external application. How do I work around this being a reserved word?
I reconfigured everything back to using ConnectionID and I must have had something wrong, it is now working. Thanks for all of the comments.