I wanted to withdraw a little XTZ from delegation, it turns out that the Galleon wallet is not serviced (that is, it supports it until December 20 - but what is unclear). You can log in, but then you can't do anything. I imported the key to the Tempe wallet - but removing it from delegation to withdraw is also a quest. Maybe someone has encountered this lately?
As far as I know you can't undelegate using temple wallet (either browser or mobile version) : in case you need to withdraw some tezzies you can move your funds to the new address which doesn't have a delegator. Not sure if you can move all your funds or you should leave in the wallet a little bit like 0.0000001 or so, cannot remember it by hand.
Anyway if you use telegram search for @MadFishCommunity and I think they can assist you quite quickly.
hope this helps