Patch up

Patch sth up: To try to improve a relationship after there have been problems.

Usage:
Jackie and Bill are still trying to patch up their marriage.
Did you manage to patch things up with Jackie after your row?

Excerpts from soaps, novels and films:

Bold and the beautiful
“Taylor: Rick had suggested that Ridge was the one who may have killed Shane, and Phoebe didn’t handle it well. She handled it rather badly and she ended things.

Brooke: But now that she knows he was right, that Ridge was involved somehow, maybe they could patch things up.”