Paypal Error with Fundraising Plugn

I'm getting the following error when the user is taken to Paypel and tries to pay via Paypal for the fundraiser:

Sorry — your last action could not be completed
Error Message
Your request failed due to technical difficulties.Please try again after some time.

If you were making a purchase or sending money, we recommend that you check both your PayPal account and your email for a transaction confirmation after 30 minutes.

If you came to this page from another website, please return to that site (don't use your browser's Back button) and restart your activity.

If you came from PayPal's website, click the PayPal logo in the upper-left corner to return to our home page and restart your activity. You might have to log in again.