DB21034E The command was processed as an SQL statement because it was not a
valid Command Line Processor command. During SQL processing it returned:
SQL20241N Writing a history file entry for dropped table
"{tablename}" failed. SQLSTATE=560C2

I also face similar error related to history tables when I take Backup

SQL2048N An error occurred while accessing object "db2rhist.asc". Reason
code: "2".

Can somebody suggest me how to resolve these errors.

You can disable drop table recovery on your table and issue the drop command to work around this error.

But, make sure you look at the db2diag.log to check why the file is not accessible.

Can you please let me know how to disable
drop table recovery on tables ?? Will this solve my error related to backup as well ?

Check the "alter tablespace" SQL statement in the manual.

Disabling drop table recovery won't resolve the error related to backup, backup operation needs to update the history file. As Sathyaram said, check the db2diag.log to understand why you're getting this error.

What you may try to do is to rename your existing history files (db2rhist.asc and db2rhist.bak) located under the db directory of this db. DB2 will recreate them when it needs to write to the history file.