Contest of mayors, I won but no prize

Won yesterday, 1st place in Megapolis (highest) league. When contest ended, a message appeared "You are now playing in Neighborhood (lowest) league" and no prizes given.

I found the same issue happened to many other players, over many years, but seems like it was never resolved.

Support chat said they can't help. In-game chat isn't responding.

Example of the same issue:

Contest awards not given very weird bug ??? | EA Forums - 10435568

Is there anything that can be done? Was anyone able to resolve this?