LibGit2Sharp.LibGit2SharpException | too many redirects or authentication replays

I am using LibGit2Sharp (version 0.28.0) with a Personal Access Token to access AZURE Repository.

UsernamePasswordCredentials =>
{
Username = "pat",
Password = PersonalAccessToken
}

CustomHeader => "Authorization: Basic {Convert.ToBase64String(Encoding.UTF8.GetBytes($":{PersonalAccessToken}"))}"

Everything was working as expected until last week, when I started encountering exceptions while trying to interact with the remote repository (e.g., clone, pull, push).

Clone failed. | LibGit2Sharp.LibGit2SharpException | too many redirects or authentication replays
at LibGit2Sharp.Core.Ensure.HandleError(Int32 result) in //LibGit2Sharp/Core/Ensure.cs:line 154
at LibGit2Sharp.Core.Ensure.ZeroResult(Int32 result) in //LibGit2Sharp/Core/Ensure.cs:line 172
at LibGit2Sharp.Core.Proxy.git_clone(String url, String workdir, GitCloneOptions& opts) in //LibGit2Sharp/Core/Proxy.cs:line 278
at LibGit2Sharp.Repository.Clone(String sourceUrl, String workdirPath, CloneOptions options) in //LibGit2Sharp/Repository.cs:line 824

Start with the reported call path in Core/Ensure.cs, Core/Proxy.cs, and Repository.cs, focusing on Repository.Clone in LibGit2Sharp 0.28.0. Reproduce the authentication failure against an Azure repository using the shown credentials and headers, then document the cause and verify that clone, pull, and push no longer produce the reported exception.