I have both an online store and POS, neither use Shopify-Payments. I am using Stripe and PayPal for processing sales. I need a credit card reader for the POS system and it seems I can not use the Shopify hardware (card reader) as I am not using the the Shopify payment system (Shopify-Payments). Is this correct? I contacted strip about a credit card reader and it seems they only off CC Readers for their own POS system and I need payments to still go through Shopify to track them and handle inventory.