Has anyone else had this experience?

Made an Amex request to pay my Gold card. ACH pulled from HSBC and posted. Next day, credited back to my account.

I received an email from AMEX saying insufficient funds (not true) and that they will reattempt. Called HSBC and they confirmed that I had sufficient funds, they authorized AMEX's pull and paid, and that AMEX was the one that returned the payment to my account.

Now I'm just worried there's a negative mark in my relationship with AMEX... because of AMEX's own system error...