[MASTERY SYSTEM] Getting an S while ranking up to rank 5 incorrectly displays Mastery 6 tokens

If a player ranks up a champion to mastery level 5 and also gets an S-, S or S+ in the same game then the client will display that the player has obtained a Rank 6 mastery token for that champion as it would normally for getting an S. However if the player checks their Loot and crafting inventory the respective token will not be there.

1. Play a champion that is about to rank up to mastery level 5
2. Obtain an S- or higher
3. Complete the game and go back to the client as usual.

The message should appear saying you have achieved rank 5 with that champion and then after accepting that you should also get the message saying you have a Mastery 6 Token. Even after accepting that message if the player goes into their Loot and crafting inventory the mastery token will not be there and the player will have to earn it again.

As of right now I don't have any screenshots but this has occurred to both me and my friend each time we have gotten an S while simultaneously achieving rank 5