Answer: resealed

AnswerCrossword Clue
RESEALED

Closed again, as a plastic bag

RESEALED

Zipped again, as a storage bag

RESEALED

Applied more caulk

RESEALED
Closed up again
RESEALED
Closed again.
RESEALEDClosed an opened envelope
RESEALEDClosed anew
RESEALEDTwice-secured
RESEALEDMade more waterproof
RESEALEDClosed after use