Issues with sex

I just started seeing someone new, we really like each other and have been very close for a long time now. We hooked up a couple times and everything was great, but one time he wasn’t able to perform and he hasn’t been the same since. Like I can only keep him going for a few seconds before we have to stop. I’ve been with other men before and it’s never been a problem so I don’t think that I’m causing it. Looking for advice to help him out.