Miscarriage 9 Weeks

Br

Sadly after seeing the heartbeat at 6 weeks I went for my 9 week appointment today and although baby measured exactly 9 weeks, there was no heartbeat present anymore. Devastated as this was a PGS tested embryo, and my last. Trying to understand what could have gone wrong this time as I have a healthy baby from my first round.

Anyone ever experience a miscarriage after seeing the heartbeat?