Hi Cheuhimho,
Great question! In some situations, the store will as for a receipt.
Best option that I can see is make sure you have Find my iPhone turned off, you are backed up and ready to go.
If they do ask for the receipt, tell them that you purchased the device from their store (if at highpoint) and they will be able to locate the receipt.
Apple will give you a hand here, after all, they want to create a happy customer.
be sure to book an appointment and I hope you get your phone fixed!
For more information on getting your phone ready, check out this article: Get your iPhone, iPad, or iPod touch ready for service - Apple Support
PS: The reason I say make sure it is ready is because if you have Find My iPhone turned on, they may ask for Proof Of Purchase (ie, receipt).