Hi, BES3.

I know how important letting your customer enter their card information. I here to clarify and give more details about entering customer's details in QuickBooks Online.

Currently, the option to let your customer enter their credit card information on their profile is unavailable. Instead, you can sign up for a QuickBooks Payment account to let your customer pay their invoice online. They'll be the ones who will enter their credit card information. I'll show you the step-by-step process.

Step 1: Sign up or connect an existing QuickBooks Payments account:

1. Sign up for QuickBooks Payments.
2. Sign in to QuickBooks Online as an admin.
3. Go to Settings ⚙ and then Account and settings.
4. Select the Products and services tab.
5. In the window, click the QuickBooks Payment account you want to connect. Then choose Connect.
6. Review the account info and make sure it's accurate. If everything looks good, hit Connect.
7. Once done, sign out and sign back into QuickBooks Online.

Step 2: Set up online invoices so customers can pay online:

1. Go to the Gear icon on the toolbar.
2. Select Account and settings, then the Sales tab.
3. Under Invoice payments, click the pencil to edit your selections.
4. Once done, hit Save.

Once done, you can create an invoice and send the invoice to your customer. Then, you can ask your customer to follow the link in the email and finish paying their invoice online. For your reference, you can check the steps in this resource: Take and process payments in QuickBooks Online.

In addition, I've included this material that contains detailed information about recording invoice payments manually: Record invoice payments in QuickBooks Online.

I've got your back if you have any other questions managing your customer's profile or any QuickBooks-related concerns. Just add any details below and I'll get back as soon as possible.