This might be on a low side importance, and only usefull when you are leveling a new character stacking quests before using a Battle manual.
My suggestion would be that, when you click on a mission board and you have some completed quests ready to claim, that it does not complete it when you click on it, but instead have a dialogue option in the dialogue box of the board like "Complete all", just like the "Take all" option. And ONLY if you click on complete all, all the quest you have completed would be redeemed.
Exemple : ![https://i.imgur.com/HzvXdFg.png](https://)