@magicalmoons As others have mentioned, there could be many factors outside of your weight and typically there aren't fertility concerns unless it takes over a year of ttc.
It sounds like you're doing everything right and this very well may be out of your control or a matter of time/many attempts, as frustrating as that may be.
Ultimately it couldn't hurt to try to lose weight, if you suspect that could be a factor, as long as you do so in a healthy manner. But please don't blame yourself/your weight if that's the approach you choose. I like to view it as an opportunity to fit in some extra activity prior to not having time/energy to workout while pregnant or taking care of a newborn.
I myself was heavier than you (around 250lbs) and was actively trying to get into shape (aerobics every other day) when we started trying. I figured I'd have more time to get into shape since I was early 30s and obese, but we conceived way sooner than I expected. Since then, my energy was zapped and I haven't worked out other than going for long walks. Even though I'm no longer pregnant, I'm sleep deprived and lack energy/motivation to workout.
All this to say, it's likely out of your control, but you can look into fertility (if it takes you 4 more cycles with no luck) and working out more may help or it may just be a good distraction/opportunity. Hugs.