As for repair, look locally for a reputable shop that does micro-soldering repairs. Ideally, you want to find someone local but good workmanship trumps locality. There are many shops worldwide that do this so you shouldn't have any problems finding them. Talk to them and ask how they do their work. Focus on troubleshooting, as opposed to shotgun replacement, and good practices like proper cleaning of boards once completed etc.
If you can't find one locally, then consider mail-in repair. There are several [https://www.ifixit.com/Business|reputable] micro-solderers patrolling this forum. You can also click on my [https://www.ifixit.com/User/About/1395548/Minho|profile] to learn more about my services, at the very least, it can serve as a data point.