So many guilds lost some, if not all of their guild bank items with the TWW expansion (pre-expansion perhaps as well) due to some bug on your end, possibly tied to the bugged Warband Bank when you initially tried to release it. It has been over a month with basically zero communication on this issue, other than you "fixed the underlying issue". However...restoration of lost items has still no communication, and guilds still aren't sure if it's safe to use their own guild bank.

Guilds have lost tons of valuable items, accumulated over the years they've been playing. Players are unsure if they should be using their guild banks anymore, for fear of borking a recovery. And yet you still stay silent.

Players have spent years accumulating things. You owe us an explanation, timeline, etc. At the very least, you can let us know if this is recoverable or not. It's time to be transparent, we all pay for your service, the least you can do is let us know what's going on.

I have personally lost everything in my guild bank. There is a massive bug report post on Blizzard's forums that show that many others have the same experience: https://us.forums.blizzard.com/en/wow/t/guild-bank-missing-items-what-happened/1918643 and there are no Reponses from Blizzard.