Importing from Fogbugz gives 422

Currently we have several repositories hosted in Fogbugz, and I’m working on importing them to a locally-hosted gitlab instance. When I use the import tool, I can successfully access our Fogbugz site and map users, but when I try to click “Import” on a specific repository, I get the following error:

An error occurred while importing project: Error: Request failed with status code 422

If anyone has any ideas for fixing this, please let me know.

Edit: When checking the log, I see the error message is:

response":"{\"errors\":\"Import url is blocked: Host cannot be resolved or invalid\"