Bitbucket Commit/Pull/Push/sync Issue with Visual Studio 2015/2017/2019

Question

We are facing this issue for a very long time. All of a sudden Sync/Commit/Push/Pull operation stopped working with Visual Studio 2015/2017/2019. This happens only with Visual Studio 2015/2017/2019. If I try using Git-Bash or Source tree, It always works fine. Visual Studio is a community version.
We are using Bitbucket. Every time it is asking about bitbucket username and password. We have provided the correct username and password. There is no issue if one time I sync using source tree.

Error Seems like :

This is an error occurring. This is an error occurring.