Have also been having this issue but finally figured it out. Go to settings on your Ipad or other device that you host shopify on, scroll to the shopify pos app and make sure all buttons are toggled on. "Allow Cross-Website Tracking" was toggled off ...

Have also been having this issue but finally figured it out. Go to settings on your Ipad or other device that you host shopify on, scroll to the shopify pos app and make sure all buttons are toggled on. "Allow Cross-Website Tracking" was toggled off ...