I wouldn't be able to recommend one payment provider over the other; however, you can view a full list of payment providers for the Dominican Republic here.
You'll want to ensure the credentials you entered are correct and that you're using a valid, supported payment type for the payment provider when testing the purchase. If you continue getting an error after ensuring your credentials then I would recommend reaching out to the payment provider you have enabled as they'll be able to troubleshoot this further.
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