Double parent after a merge seems to block the pull from another person

Hello

I have a question : We are two persons working on the same remote repository My collegue update the remote repository with his ast changes Meanwhil I have done a git flow feature that I have finished then I pulled his last version from the remote repository (git pull origin develop) I had a few merge conflicts that I solved Then I did another flow feature and I finally closed this feature and push it to origin develop My collegue then try to get the new remote repository but he told me that because there were a double parent in my merge commit (but the very last commit is single parent) he could not get the last version. I manage git with comitin QtCreator and git bash command when my collegue use Visual Studio to manage git.

Is it true that a double parent is a problem to get a the last commit on the remote origin develop ? and in this case how to avoid double parent ? or is there something else going on ?

Best regards

Olivier Paillat