I have a HOTPOINT Natural Gas water heater that has worked great up until this morning. I noticed the water was warm and not hot like it usually was. Well, about 15 minutes later it was completely cold. My fiance has tried lighting it repeatedly but to no avail. He follows the instructions PERFECTLY but still nothing. I’m starting to think that something else is wrong with it. Please, if you can help us, let me know. I’m desperate!