Communism always needs to be enforced, it doesn’t happen naturally. Capitalism does. That’s why I don’t think communism can exist along with anarchy.
Capitalism also has to be enforced.
What do you think all those counter revolutionary insurgencies like the bay of pigs invasion are?
Or the state crackdowns on communist groups like the red scare?
Capitalism is not a natural state that things can revert to, it is a system that needs to be imposed.
You’re right, I don’t have much knowledge of anarchism’s philosophical framework, but I do know that the definition of the word means that there is no authority.
Anarchism is the absence of involuntary hierarchies such as the state. Authority and authoritarianism is meaningless in drawing a dividing line between ideologies because every socioeconomic framework needs to defend itself from being undermined one way or another. A good place to get started on this matter would be On Authority by Friedrich Engels.