Hi Melissa,
Is there a certain error message that these people said that they are receiving when they try to pay? If so, please share it, as well as any other specifics on when exactly in the registration process they are encountering this error (ex: are they entering in their credit card information and then getting the error or is it happening earlier on in the registration process, etc.) and that will help us investigate further.
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Julia Plymack
Senior Client Success Manager
Cvent
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