Problem with disk repair
Honestly the best bet is to copy the files on that disk elsewhere, reformat your disk and then copy the stuff back. That would be your cheapest and safest procedure.
The next thing to do would be a third party disk repair tool. I use DiskWarrior and as it is an HFS disk it will work fine (DW doesn't work on APFS disks) There is also TechTool Pro, Drive Genius and others. But I have no specific experience with those.