Sending good vibes as I write. ๐งกโจ๐
I guess you have already well explored all the possible reasons, there's a few here that I found in case there's anything there you may not have considered https://www.parents.com/getting-pregnant/fertility/5-infertility-symptoms-you-should-never-ignore/
Wishing you both the very best of everything and a home full of children and love. โค๏ธ