My Fiancee Tested AA For Genotype When Young, Now She’s Testing AS 

My fiancée and I have been engaged for about 7 months now. About when we started, she told me her genotype was AA of which she showed me the test result so I never really took it upon myself to confirm mine which I had been believing as AA. 

Recently I went to confirm mine and it turned out to be AS. In shock, I asked her to recheck hers since the result she’d been working with was from when she was a baby. She checked at the first hospital and it surprisingly turned out to be AS. Immediately she did another one at another hospital/lab and it still came out as AS. 

I know what most people will say is that that’s the right test and we are not compatible medically (which though gruesomely painful, I understand). 

but my questions are then these: 

1. How do genotype test results change over time? I know they don’t since it’s based on genetics but how on earth was it possible that she tested AA before but not now (my head is so messed up right now). 

2. I know the plain, straightforward answer for situations like this, for most people, is that we path ways due to the outcome of our genotype and I get it. But I want to ask, is there any possibility of an alternative at all? Maybe something that’s not so conventional that some people in such situations have done to help them still marry and bear children without issues. 

I understand if you think this question is stupid but I’m am a possibility thinker and I know that the world/internet is filled with possibilities.