Either ten or fourteen days ago now (I deposit at guts on Mondays and Thursdays but don't remember which this was) I deposited at guts and got a feature on royal masquerade. I think I was being $2 a spin and my balance before the feature was $160. During features on this slot if you get a mask you get another free spin, I'd had a few masks and then on the last spin I got another one which should've added more spins but it showed the "you have won $x in free game" placard except it was blank and the spins continued on in the background behind the overlay. My balance got to at least $211 during the games before the overlay obscured my view.
When the feature did end for real the game said an error had occurred and that I would be contacted. My balance was reset to the pre-feature amount ($160) and logging back into the game did nothing to help. I contacted customer support who assured me they didn't need any info from me and that they would send the report onto the game provider. I sent two emails in the following week asking for a timeline or estimate on resolution but received no reply. When I went to live chat again they said they had no record if the emails or the malfunction complaint. At that point I was getting very frustrated. Eventually I got anther email saying the same thing they had originally said: "we've sent it to game provider, we don't know how long it will take".
I'm hoping that posting this might get the issue resolved or at least some idea of when it may be. In the meantime I have stopped depositing with guts as I've lost a lot of money there, never withdrawn and with this latest issue see no reason not to go elsewhere.