My Lightroom Catalog has been corrupted and the software itself has not been able to fix it. Any ideas? Does adobe have a service where it can fix the file?
You need to find a recent backup of your catalog file and restore that.
No Back up...any other solution?
Since you have chosen not to have backups available, you are now pretty much out of luck. I am not aware of other solutions.
Backing up your critical files (not just Lightroom Classic files, but all files that are critical) is such a basic thing in the world of computers, you really ought to begin doing this without hesitation and without excuses.
Without a backup, you are pretty much out of luck.
File corruption is often a hard drive problem. I would recommend running a deep scan to find and fix any problems.
For the fun of it, Mac or Windows? Which version?
Two things you can try:
1) Press and hold the Alt (Win) / option (macOS) key while launching Lightroom Classic. In the Select Catalog dialog box, select the catalog which is corrupt and check Test integrity of this catalog option.
2) Create a new catalog File> New Catalog. Then File> Import from Another Catalog and select the corrupt catalog file.