two samples to solve situations where repositories have been imported instead of forked

bringImportedRepoBranchesBackToForked.sh

git remote add downstream UrlOfImportedRepo
#foreach branch you want to bring back
git fetch downstream/branchname
git checkout branchname
git merge downstream/branchname #hopefully your history is not a mess and you don’t have conflicts to handle
git push origin
#end of foreach
git remote remove downstream

updateDevelopersRepoAfterMigration.sh

git remote remove origin
git remote add origin "new url of the repo"
git fetch origin
#for each branch you have locally (the ones in white when running git branch -a)
git checkout branchname
git branch --set-upstream-to origin/branchname
git pull