DB2 Tablespace in state Restore pending
May be you didn't do a restore, but someone surely did, as the indicated tablespace state is only possible when a redirected restore has been initiated -- this is well described in the manual.

Normally to complete the redirected restore you will need to issue SET TABLESPACE CONTAINERS FOR 6 USING (PATH '/whatever'), where "6" is the tablespace ID, and similarly for all other tablespaces in this state, then run RESTORE DB yourdb CONTINUE to complete the operation (details here).

However, since you apparently don't recognize this restore operation, you'll probably want to abort it instead: RESTORE DB yourdb ABORT.