Checking in to right repository and valudation

How to ensure that the team members upload the code ( using visual studio ) only to authorised repositories and not to anywhere else ( personal repos, external drives, external emails ). Are there inbuilt tools or third party integrations which can give monitoring , alerting and control functionality.

The browser based and end point DLPs do not meet 100% functional needs.

The sensitive source code needs to be protected 100%.