Debit Card Payment not accepting my cardholder name

[full vessel]

I have been trying to pay for rainbow cards with my VISA debit card, and when I try to input the cardholder name, it tells me to input it exactly as it is in the card. I think the issue happens because the textbox does not accept commas, and in my debit card the cardholder name is [LastName], [FirstName] [MiddleName]. I've tried to input it without the coma on any way, but payment fails. Thank you in advance for the response