They usually have kits of screws based on which phone your working on. eBay generally has it for pretty cheap, just search for pixel 2xl screw set, and they’ll pop up.
Look on the bottom of the phone, on the left of the charging port there is a black hole/dot.this is the microphone. Is there any foreign object obstructing it? If so remove it. If not then unfortunately it must be damaged, I would recommend taking it to a local repair shop to get it diagnosed.
I was curious myself and I tried looking for new techniques online. Couldn’t find any. Finally about a week of exploring the interface I found the solution!!!! Hold down the home button to trigger Siri. Raise it up to your ear and ask a question. She answers using the ear speaker! This will also test the proximity sensor. Ps: You’re welcome!
Sorry buddy, logic board. It’s the beginning signs of touch disease. You could microsolder a new chip but it’s much too complicated. Edit: like puffs commented, you could shop around town to get someone to do it for you. If you can get a good price go ahead. But keep in mind a used 6 only sells for around 80-100 nowadays.
The iPhone 5 had a similar issue. It was only solved when you do a reset through dfu. After doing so it would give a no sim error. After removing and reinserting the sim it would work normally. I’m not quite sure if you would want to try this with the SE. but it is a major headache. Sometimes apple gets on my nerves.
Replace the proximity sensor cable. Then do a full restore via iTunes. It’s a hardware issue that caused a software glitch. Also try using the lcd shield from your old screen if you’re not already as aftermarket ones cause problems.