Epson TM-M30II Bluetooth printer very slow to print a receipt

[Jends]

We are using an Epson TM-M30II Receipt printer connected to Shopify POS via Bluetooth.  Regularly the receipt does not print quickly and hence the till drawer does not open automatically.  It can take 10 to 20 minutes for the receipt to print and the customer has given up waiting and left.  The tablet is right beside the printer.  The WiFi connection is strong.  The connection is active. Does anyone know if there is an option to connect the printer via a cable to the WiFi box or the android tablet as this is a real issue for our business?