Character Unlock Bug. Yeti Chomper and Frozen Citron not unlocked.

After finishing a Garden Ops match, I purchased a Wondrous Pack of Greatness from the Sticker Shop. In that pack, I received the final stickers needed to complete and unlock both the Yeti Chomper and Frozen Citron. However, after leaving the match and returning to the Backyard Battleground, I switched to the Plants side to try out my two newly unlocked characters, but neither of them was available in my character selection. I checked my Sticker Book, and noticed that neither character was actually unlocked. Before purchasing the pack, I had 5 out of 6 character pieces for both of them, but now the system didn’t unlock them and even removed one sticker piece from each, leaving both characters at 4 out of 6 pieces.
Please investigate this issue and restore the two characters to my account.