How can customers advise their credit card details on a Jotform as a secure online form?

I am not quite sure what you mean by advise?

Do you wish to accept credit card payments on your jotforms?

If that is true, please check the following two guides:

Setting Up Your First Order Form

Mastering Payment Form Integrations with JotForm

Or do you maybe wish to create a JotForm subscription using your credit card?

if so, do let us know more about your question / issue and we would be happy to assist.

No, I am not asking about receiving credit card payments online on a jot form, we already have that.
What we need is…
To receive credit card details online securely. Not a payment, just the card numbers.
This is so we can get credit card details from sponsors using our form, and then we set up an authorised credit card withdrawal for monthly payments from the sponsor. The sponsor is not making a payment at this point, just advising us the card details.
Thanks,
Bill

PO Box 387 Nairne SA 5252
72 Main Rd Nairne SA
+61 8 81880398
www.ahi.org.au
...

Hello Bill,

Unfortunately our terms of agreement forbid collection of credit card details using our forms as this is considered sensitive information

OK, thanks for reply.

PO Box 387 Nairne SA 5252
72 Main Rd Nairne SA
+61 8 81880398
www.ahi.org.au
...