[Koha] Checkin error

[Arshad Iqbal]

Hi to all.
I am using koha 19.05 on Debian 9. When i try to checkin an item i am
facing this error ,
Software error:

DBIx::Class::Storage::DBI::_dbh_execute(): The user specified as a
definer ('root'@'%') does not exist at
/usr/share/koha/lib/Koha/Object.pm line 155

How to solve this problem?
-- 

Best Regards
*Muhammad Arshad Iqbal*
*Assistant Librarian*
*NUST Central Library *
*National University of Science and Technology (NUST)*
*Sector H-12, Islamabad, Pakistan*
*Tel. Office:051-90851087*
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