Do you have a warranty like the 1 year manufacturer warranty or say the sprint $7 per month asurion warranty?
How long have you had your phone. Generally all phones have a 1 year manufacturer warranty. Go to a sprint store or contact HTC. If it's asurion, then go to sprint.com and file a warranty claim.
Fixing it yourself or having a non-approved tech fix it will void any warranty you have on that phone.
Take it to an authorized full service store and let them handle it. They usually save you money, and they know what they're doing. If you don't have it already, the $7 monthly insurance is a very good investment. It's already paid for itself for me.