why was I charged a dollar for adding a charge card to my account

[AnnieKnox]

Why was i charged $1.00 for adding a charge card to my account?

[Amethyst Jetaime]

This is not an actual charge, but an authorization that they request from your credit card company.

Once the authorization is received, which confirms the account is valid, they then rescind the authorization.

At no time is the US$1.00 actually charged, though the authorization may appear on a credit card statement as such. The amount may show as "pending" or "authorized" for a few days, but then will drop off the account entirely.

[Rolig Loon]

Amethyst is quite correct.  That's standard business practice in many companies.  To verify that you have an account to link to, they simply charge your account a small fee, collect it, and then refund it a short time later.  That's a quick, easy way to be sure that the link to your account will work.  If you open a verified PayPal account, for example, that's what they do.