BBT graph help ?

Leasa

Can someone please help me ? I have the femometer and fertility friend app and until today both were saying I was the same amount of DPO ,well today fertility friend says I'm 5 DPO but femometer has put me back to 3 DPO I'm confused ,which one is right ? 🤔 Not been doing this long so don't really have a clue what I'm looking for 😳

Will add pics of FF and femometer BBT charts