Y’all I need HELP! I can’t google this!

I know there has to be someone on here who has a great opinion that doctors can’t give!

Ok so here’s the low down! I’m 26 and have been TTC since August of last year which has been 11 months now. I got pregnant in November (3 months after TTC) and had a miscarriage in December. I haven’t been able to get pregnant since.

I’ve been in to the doctors multiple times and as far as they can see I’m healthy!

•I have regular periods and I have tracked ovulation and it seems I am ovulating!

•i dont have endometriosis or anything

•My husband has above average sperm count so he’s good!

What am I doing wrong?! If I was able to get pregnant once, that means I am fertile and able to conceive right?