This issue was identified in a release of the plugin where the fundraiser's constituent ID is getting added gift attributes. The plugin is incorrectly assuming the IDs are numeric. If a constituent has any non-numeric fields in the fundraisers constituent ID the import doesn’t save the gift and returns the exception message.
We have evaluated this issue and have determined it will not be addressed in the program in its current state. In this case, we believe the risks and challenges outweigh the potential benefit of resolving this issue. We strive to select the most impactful changes and issues to address with each release to accelerate the rate at which we deliver new features while sustaining the highest level of quality for our customers.
Some users find they can update the constituent ID for the fundraiser (which is defined in the exception error) to remove the non-numeric character. For example, there is a business rule to include the Current Year prefix and a separator like "-" when creating a new constituent record, you can just remove the "-" from the constituent ID, and the gift will update.
If you are unable to edit the constituent ID, you will have to enter the gift manually.