When you connect the ProPay integration you are provided with an introductory pair of transaction limits: one per transaction and another per month. ProPay includes these rates as part of the account creation process to get you up and running with their service quickly however this limit is just a placeholder.
If you would like to increase your transaction limits you can contact ProPay at limits@propay.com. A representative of ProPay will work with you to increase your limits.