When payment mysteriously is missing from my account, without any notice, it's attempt of scam. Those who complain, will probably receive missing amount, but anyone who isn't, they'll keep their earnings. So, not sure how that works for you... but that's attempt of 'oopsy - daisy' scam.
It's the oldest trick anyone with affiliate program is using. It looks like they are innocent, but code doesn't fuck up itself. It's machine, that works the way how they program it.