Probably, it's down to your connection string: you are likely - for development - to be using a local installation of SQL and connecting to it via "localhost" and using integrated security.
That's not correct for production: they need a centralized SQL Server instance, and "proper" username / password combos which give them just enough permission to do their job, no more.
And that means they need a different connection string - they should never be sharing the SQL server instance you use for dev as there is far, far too great a change of your code modifications damaging production data.
Hopefully, you have written your code without "hard coded" connection strings and it's just a case of changing your config files to reflect the new info
Here's how I do it:
Instance Storage - A Simple Way to Share Configuration Data among Applications[
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