We are currently aware of an issue were receiving party chat while opening chests will result in being stuck. The rewards for the chest are given to the account on the server, but you won't be able to see receiving them. For the time being, we would urge you not to open chests while in a party.
If this occurs to you and you want to know what you received from your chest we can look it up for you if you reach out to us by submitting a ticket.
Please be sure to include the type of chest, the day/time you opened it, and the time zone you are in.