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You can if u want, its just a air bubble from when it was glued originally. Probably why it let go, in the first place.
It wasn't properly glued, then dropped, and came apart.

1st one looks good

2nd I'd say it was left in a mug, and dried. Give it a good soak in hot water ( not boiling hot ) and a bit of hair conditioner, let it dry upside down, still wet and stuck...