I did the same with an S5 with a worn otter case. Following YouTube instructions, I removed the battery, and used a vacuum cleaner at all openings. It worked!
If you go visit a elderly relative who lives rural, has no computer or Wi-fi, barely has cell service, be sure to turn off the feature on your phone or you will have a dead battery as it continues to search for a Wi-fi open connection. Happened to hubby this last week, thought he was going to need a new phone or battery at the very least. Turns out the house down the road had an stupidly OPEN no password protected Wi-fi to far away to connect to, but the phone kept hunting for and trying to connect to, drained the battery in a short period of time.
And watch your phone bills if you visit areas like Niagara Falls, walk down town, and one step you are on a US cell tower, next you are on Rodgers, and it reflects on your phone bill as international call, if you make a call while still in the USA if you walk into a Rodgers cell area.
He’s home now and phone works fine as we have Wi-fi.