I have owned every Samsung Galaxy Phone using Verizon as my carrier. My S7 now has the case open from the Battery swelling inside. It appears neither Verizon nor Samsung offers any Solutions or even warranty to these Samsung Battery defects. Any suggestions from community, I was going to get the S8 soon but don't want my house to burn down.
Defects are covered under the 1 year manufacturer warranty. That certainly could be a hardware defect, however swollen batterys most commonly occur due to user issues like overcharging, using a non authorized charger, trauma to the battery from a drop incident or simply age of the battery after so many charging cycles.
The cheapest solution would be to have the phone repaired at a local electronics shop, or sending it to Samsung so they can repair it.
Sometimes I really miss removable batteries, as switching them out was so easy and fairly cheap if something goes wrong or as it ages.