Late BFP?

Liza β€’ πŸ‘Ά 5/5/16 πŸ‘Ό 8/15/18 πŸ‘ΆπŸ»πŸŒˆ due 12/15/19

Anyone ever got a BFP after a week or more after your missed period?? Currently 9 days late for my period and testing bfn! If you got a BFP late, what was the cause?