Dominaria United Mythic booster packs switched to regular packs on PC

I purchased x3 Dominaria United Mythic packs on My PC (Windows).

packs purchased with in-game currency, not gems.

I opened the first pack, but was not rewarded with a mythic rare.

I then noticed that the packs were the normal versions, not having a reddish banner pattern.

I went back to the store, double checking that I did indeed buy mythic packs by purchasing an additional one, using the same in-game credit.

Upon going back to the tab to open packs the remaining packs as well as the newly purchased pack, all of them were now mythic.