Partial Refund Shows Pack as Not Purchased

This is currently happening to me as well.
I purchased several packs in September 2016 on sale.  These were available to me until November 2022, when one pack: SP07 – Kids Room Stuff, no longer showed as owned.
I have been trying to figure out what happened with this and was told at the time that it had to do with Origin on Mac, so I copied the pack content over from my archive and it appeared in game as normal.

However, I have since moved to another computer and again, the pack appears as unowned.

I checked my EA purchase history and it shows this pack was issued a Partial Refund at the same time as it was purchased along with other packs which were all purchased at once, on sale.

I have been trying to deal with the Customer Service through the website as well as through the chat and have been run around in circles, no Customer Service agent bothers to read the previous communication on this problem.  In addition, I have been told by Customer Service, through another case which apparently they decided to start (I now show as having 2 open cases on this same subject as well as one closed and marked 'Solved'), that the pack was refunded and I have to buy it again.  At current, my game saves are now broken (I back up everything so this is not a total loss, but I cannot currently play the game) because of this clear error on EA's part.

I have, as you might know, gone through all of the suggested 'fixes' for this error, which is very clearly nothing to do with my install or computer (this problem is 100% repeatable on all machines I own: Mac and PC) to no avail.  I am stumped as to how to repair this issue, I have been told directly by EA Customer Service that this is my issue, not theirs.

I have attempted several times to contact someone who can actually help me and each time have been 'hung up on' or passed back to another form-mail response, rather than any attempt to fix this issue.

At this point, this forum is my last resort.