A prepaid card may be considered an account under Reg DD, but the only triggering terms in Reg DD are an APY disclosure (not applicable if not interest bearing) and bonus disclosure so unless you are providing something in excess of $10 in value for opening, renewing, maintaining or adding funds to a prepaid card, that would not be applicable either.
Look at 1030.8 for the requirements you'd need to consider.
Also review the language in the ad for anything that could be considered confusing or misleading as UDAP always applies even if there are no triggering terms in an ad.
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