Un-rehireable because of pregnancy

I had to leave Amazon because I became pregnant a year ago and I couldn't keep taking leaves without pay so I told them I would be finding a new job within my two weeks.. Well I came back through the temp agency and worked for a month, was getting sick so I had to keep going to the hospital, I had doctors notes and hospital records, got laid off anyways. Tried to come back last month they said I was unhireable because I didn't give a proper two week notice, but yet all these other people can walk out and quit on the spot and then come back within a week.. So I tried contacting the people who work next to Jeff Bezos... They didn't do anything and only told me what I already had told to me before... They made new rules right after I left stating if you're pregnant, tell your area manager and we will put you somewhere that's not stressful, my husband tried to get a father's leave for when our son was born, but couldn't. Two weeks later they changed the rules on that father's can now get a "maternity" leave too. And even though I did give a two notice, they wrote in there that I didn't, they aren't gonna hire me back because of a mishap on their end, but they will let someone who walked out on the job come back?! I think Amazon is a sexist place to work. They are unfair and don't go by the "rules" that they claim to, which is illegal.