Help a girl out

Hey guys so im 27 y.o, im severely anaemiac and have been for 10+ yrs, my HG level is 4, my ferritin is extremely low, I basically have severe anaemia. Doctors don't know why iron isn't sticking in my body but can't find out the reason. My coeliac came back negative.

I get severe headaches, I pass out, I get dizzy every time I stand up, I am pale in skin, I get tummy aches, I am tired 24/7, I lose weight unintentionally, I get extremely breathless

Im also suffering a miscarriage carriage and have been bleeding nearly 2 weeks, making my iron drop more and feeling more sick. I also get night sweats.

But there is just no clinical reason for my anaemia?

My thyroid bloods also came back clear

Has anyone had this issue? What can I request the docs to check for? Please help im sick of feeling so tired

My body doesn't absorb iron orally so I have to get an iron infusion but waiting on transferrin test results