Erro ao criar primeira branch do projeto


I’m using GitLab along with SourceTree.
I created a new project and I’m not trying to create a branch to do the first commit.
I noticed that when viewing the project through SourceTree the “master” is not appearing in the branches as usual.

I did a test making the first commit directly to master without using a branch and after this first commit the master appears.

Does anyone know how I can go back to being able to create a branch on the first commit of the project?

error that occurs when trying to create the first branch of the project:

git -c diff.mnemonicprefix=false -c core.quotepath=false–no-optional-locks branch 26297
fatal: Not a valid object name : ‘master’.
Completed with errors, see above.