You are migrating a large number of files from a public HTTPS endpoint to Google Cloud Storage. These files are protected from unauthorized access using signed URLs, which provide limited-time access control. To facilitate the migration, you created a TSV file that contains the list of object URLs, and you initiated a transfer job using Google's Storage Transfer Service.

After some time, you observed that the transfer job had been running for an extended period before eventually failing. Upon inspecting the logs of the transfer job, you found that it was progressing smoothly until it encountered a series of HTTP 403 errors, which caused the remaining files to fail to transfer. You have confirmed that there were no changes to the source system during this time. To resume and complete the migration process, what steps should you take to address this issue?