Hey @Danai_Osmond - thanks for the detailed report. I did a bit of digging and I believe this may be a separate issue from the earlier bulkCartUpdate fix
From what I can tell, , your addLineItem call looks correct, so it is odd this is occuring. Could you confirm the exact Shopify POS version on iOS and Android, and whether the variant subtitle appears on its own after roughly a minute or stays missing indefinitely?
I’ll add your report to that investigation and loop back once I have a firmer update.