Anybody else having problems lately with requesting/un-requesting upgrades through the app?

I'm FO so it is often that I'll either check or uncheck the Comfort+ request relatively close to travel, but lately it hasn't been allowing me to do so. On iOS, Android (tablet), and on the full DL.com (laptop) it simply gives me an error message and says they cannot process my request. So when I know I'm going to clear into crappy seats or if I see good ones available, I cannot change my request, even when checking in.

As a result, I'm either getting upgraded to middles in C+ or remaining on the list and have to request the GA take me off when I get to the gate. Kinda frustrating, just wanted to know if anybody has similar experience or why its happening....thanks in advance!