STILL TRYING 😞

I am 27 yrs old. Our daughter is 5 almost. He is active duty which means every two years or less he is gone for 7-9 months. We have been trying for a year to get pregnant. With my first kid it took 3 months not even that. I had all kinds of test done and im all good. Tubes open,periods 28days on a dot,5 days lasting,im not too skinny or have too much weight,my hormons are fine,he did testings on his sperm and its all good as well. At this point I am starting to be very very down and depressed. My daughter is asking for a sibling for 2 years now and I cant seem to get pregnant. Im taking prenatals we are having sex every day literally or every other day. I sleep work and eat fine. I wouldnt say i am THAT MUCH stressed to not being able to get pregnant. I just dont know what to do at this point. Please please if anyone has any advices or recommendations dont hesitate to comment. I just feel like a such a failure I dont know what to do. Not to mention my husband wants more kids and i do too. He isnt pushy about it and its actually sweet and supoorting I just feel like its my fault im the problem.