iPhone 7 Plus super laggy after water damage

Hi there and sorry that you had a technician try and fix a waterlogged phone. While it is possible to fix a phone that has been exposed to water I never do it unless I see that the water only “touched” a very few places. The reason I only fix Water Damaged phone for the sake of data recovery and not to save the phone is for the exact reason why your phone is lagging. No honest technician that has your best interest in mind would try and fix a water damaged phone for your use. In very few circumstances would I do that. As I mentioned before I’d have to completely feel 99.9% sure that only part of the logic board or flex connector actually got wet. The reason for this is that there are so many components on the phone that might fail even after a sonic cleaning and an alcohol bath. Why would I risk your data and your well being and give you a phone back that could fail. IMO that’s not good business. Sorry that you are having this issue but I’d just take it back to the tech and ask for your money back and then get a new phone. Especially if it was major water damage. Just to back up what I’m saying Jessa Jones from iPad Rehab and who’s been on iFixit does not fix Water Damaged phones for use. She and her team only fix them for the sake of recovering the data. As stated on her website. Don’t get me wrong it’s not that she and her team can’t it’s just that it’s unethical to do knowing the risk of failure.