fatal: mismatched algorithms: client sha1; server sha256

We are trying to add a repo using subtree and facing a titled issue. the command we are using is git subtree add --prefix $val ${projectGitLink[$val]} ${projectGitBranch[$val]} The single clone works fine but while using subtree it is giving an error.

How do we resolve this issue, I really appreciate your response.

Update (from #441653 (comment 2277453572))

We're combining multiple projects into one common repo where our pipeline is adding other projects using git subtree and till now we have not faced this issue with older repositories. But when adding newly create gitlab repository to the same common repo we're facing this issue.

We've raised the issue as well at #510968 (closed)

Getting an error at : git subtree add --prefix $val ${projectGitLink[$val]} ${projectGitBranch[$val]}

Our pipeline code goes like this:

for val in "${selectedProjects[@]}";
do
	if [[ -d "$PWD/$val" ]]; then
		git rm -r $val
		git add .
		git commit -m "removed subdirectory"
		git subtree add --prefix $val ${projectGitLink[$val]} ${projectGitBranch[$val]}
	else
		echo "Added subtree"
		git subtree add --prefix $val ${projectGitLink[$val]} ${projectGitBranch[$val]}
	fi
done

If you can help me to understand SHA or guide me to resolve this issue that would be really helpful.