One step dip pregnancy tests

Sam

Has anybody had issues with these pregnancy tests?

Basically I took a test 3 days ago (1st pic) looks positive, I inverted it and still showing (2nd pic) done another one next day and it was BFN, again yesterday was BFN

Today I had another one which again showed a faint line (3rd pic)

All were taken with FMU

Pic 4 is inverted test this morning, pic 5 and 6 is same test but after the time limit