First, my credit card on file, the one Smugmug charged me for the pro account only at the beginning of this March is not expired. Now, Smugmug is asking me to update my credit info as if it has no record of my credit card information. Is this a scam? Has the site been hacked?
I suggest you contact SmugMug support directly. While they do check in here occasionally you will get a much faster answer by emailing them.
Musings & ramblings at https://denisegoldberg.blogspot.com