It could be low quality adhesive. I recommend using 3mm adhesive, not the premade stuff. I also recommend to put a soft rag over the phone and leave about 10 to 15 pounds of weight on top of the phone for about 2 hours. I use 3 five pound weights that were previously used for dumbells. Hope this helps.
Okay everyone. I think I have finally figured this out. The iPhone 7 proximity sensors are adhesived down pretty well. My mistake was I wasn't heating the prox hot enough. If that adhesive isn't hot enough, when you try to lift up the proximity it may possibly cause a bend on the flex cable, which can cause the proximity sensor to lose its connection with the flex cable that the ambient light sensor and front camera are also connect too.
Try going into control panel, then into devices and printers. If you see the iphone under unspecified, then right click it and select troubleshoot. If it doesn't give you the option to enable the device , then right click the device, select properties, click on the hardware tab, then select the properties button at the bottom right. Then click change settings, click on the driver tab and click disable and then click enable.
Hey Billy, sounds like your battery is having capacity issues. Lithium ion batteries are ranged to last from as little as 1 year, up to 5 or even 6 years. (Mainly flip phone batteries may last that long) It really just depends on your charging habits. Try not to plug it in until it reaches 20 percent or below and try to leave it plugged in until it reaches 100 percent capacity. If there's a local Batteries Plus Bulbs/We Fix It in your area, you'll be able to get a great deal on a battery. Order it on batteriesplus.com and you'll even get 10 percent off! Don't trust the 10 dollar ones you can buy on ebay. The battery from BPB will also be lifetime warrantied through any of their stores. They can install the battery easily for you if needed, and if the phone continues to cause the same issue, you will have a 14 day return period. Hope this helps!