So I just get a letter saying my credit card account is past due. DS and DIL use this particular account. I check it on a regular basis. I just got an email yesterday that a payment was made. So I knew it was not past due. I went to the website and sure enough, the phone number on the letter is not the number on the internet. So I contacted a rep via live chat. She assured me that my account is up to date with no issues and to disregard the letter.
BEWARE of any letters stating that your credit card is pst due when you KNOW it is not!