NAV 2017 upgrade error while Sync tenant

Hi All,

I am doing an Upgrade in NAVISION from NAV 2013 R2 to NAV 2017. After importing all the customized objects and the upgrade toolkit objects in my NAV 2017 database, and when i run the Sync - NAVTenant i am facing the below mentioned error

The following SQL error was unexpected:
There is already an object named 'CompanyName$UPG Posting Exch_ Column Def' in the database.

I am unable to proceed further and i don't know how to solve this issue...Please kindly render your timely help.

Very Eagerly awaiting a solution...