A situation like that can be expected to be cause by a library failure, or failure of the path to the library. Use the library Web page or the mtlib command or similar to check out the condition of the library, and proceed from there. Do research in your TSM Activity Log and operating system event log to see what happened to the library, when.
Note also that you are running with NO maintenance on your TSM server, which is highly undesirable. Richard Sims