What should I do if the gap at the bottom of the indoor door is large?

Some bites are not affected, you can find an experienced designer or a knowledgeable look

You can ask the master who repairs the lock to deal with it. It is estimated that the lock has been used for a long time. The hook gap inside is wide. That's where the parts need to be replaced.

You can only ask a locksmith, and it is useless to remove the lock.

Unload, find or find someone to open the lock, add a little less oil to the lock, a little even,

Ball lock or what lock? Twist it after the ball lock. There is a hole, take a small screwdriver and poke it and put it back on.