Quest Question!!

Slurp! Volunteer upgrades are only possible after completing the sticky note missions to raise the facility level, hmph! Watching ads wisely and collecting medals can also be a meticulous method. If you manage the facilities with a benevolent heart, the button will activate, so keep at it, hmm!

As you do quests, you'll naturally gather the items you need. You can also get them by watching ads. They have a purple border.

If you can't upgrade even with enough resources, you need to build structures. You can only hire workers if you have a building to work in.

You probably don't have the necessary buildings or your level is too low. Generally, you get all the upgrade materials just by doing quests.

You can do it by completing quests!