Chosen Solution
A few weeks ago my home button stopped working, and I survived by changing apps by turning off and on my iPhone. Now, however, my power button has stopped working. I’m going to be near a Mac store soon, will they fix this for free? Also, how can I fix this myself?
There is a simple fix for the Power Button which sometimes works. Tightly hold the top corner of the iPhone together near the Power Button pushing the front glass and back casing together. At same time press the Power Button. If it works great. Then you can carefully Super Glue the back case to the bezel in this corner. A sparse amount of glue is all that is needed to hold that corner together, be very careful. Good luck.
Maybe you need to take your iPhone to the repair store. We cannnot fix home button on ourselves.