I am trying to enter a mastercard manually but it won't take all 16 numbers on the card.
16 digits is correct and MasterCard numbers must start with 50...., 51...., 52...., 53...., 54...., 55.... OR new in 2017 in the range of the first 6 digits 222100-272099. Make sure you are starting with one of these numbers or otherwise it won't accept it as it is likely fraud.
I just updated square on my WooCommerce site. It won't allow me to enter all 16 digits of a credit card... Only 15. In your community chat, same issue was for someone with a mastercard. I am trying to enter a visa. I am not convinced the help they received was the issue.
Did you ever get your issue resolved? Could you share what it took to fix the issue?
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Sorry to hear the trouble with this. From this page it looks like this could possibly be a known WooCommerce issue. I would suggest contacting them for support. If a solution is found, please reply back in this thread.
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