[Koha] Cannot restore my old koha db to a new installation

Hello community, I have done a fresh installation of the koha 18.xx but when I tried to restore my old koha(3.xx) db from a MySQL dump I am getting errors on reaching the upgrade schema library. We are using Ubuntu 16 and have also installed MariaDB. The error I am getting is *DBD : :mysql: :db do failed: Table 'koha_cpgslibrary.systempreferences' does not exist [for statement "Select " FROM systempreferences WHERE 1=0" ] at usr/share/koha/lib/koha/Database.pm line 110.* *I also tried without upgrading the schema but I am getting a Dbix error * What should I do to be able to restore back the old db. Thank you Larisa