Currently in the game as you perform certain activities, quests, dailies, etc... you are awarded keys. At rare occurrences you can also receive key tokens while actively playing through skills or PVM drops. At a certain point though, there exists a limit on how many of these key tokens you can receive until you have to use currently acquired keys to "make space". Additionally, if you have reached the limit for key tokens your drop rate for key tokens appears to be increased (based off my observations), further exacerbating this annoyance. I understand that this is a way to incentivize players to use keys, but the cap on this should either be removed or increased.
I don't speak for all players, but I try to save my keys for certain Treasure Hunter events. And I don't think my ability to stack keys should be hindered by this mechanic nor should I feel like I have to choose between using up multiple keys to consume this token or just destroy the token in its entirety.
If this original option doesn’t suffice then an alternative ought to be that key tokens are removed from the drop table if and only if you are at the key token limit.