Need help some advice please

So me and my boyfriend been together since 4th July of this year and when we first started talking and being around each other we didn’t have much of a problem when it came to sex he does have health issues with seizures and I looked it up and it did say it can effect them having sex but I done try everything nothing works to turn him on like one day I got all dressed up to go out guess that turn him on we started kissing and we had sex yesterday morning give him head while he was on the phone it was hard but then it went soft and he was like wasn’t accept that so at this point is it me or him with the problem