Can anyone explain to me what it means when a donors donation didn't go through and was "restricted"?

 We work with a number of payment gateways and payment networks to support your merchant relationship.   They spend billions on fraud detection and prevention, however, it can be costly for nonprofits when bad folks are using the simplicity of our forms to do a "card run".   We have added a patented layer of cardholder and merchant protection to leverage the payment gateway and network information to prevent "card runs" from impacting our clients.  One technique we use is to look at the source of the request including IP address.  If a legitimate donor has been flagged as RESTRICTED, please contact support to address it, however, keep in mind the donor may need help with entering their information and becomes a great relationship building opportunity.  We see less than 1% false positives (where a legitimate donor is restricted), but it does happen, so please be patient as we correct the situation and know we are doing it to protect you and your donors.