It depends of your character.
In general, the main character is a blueprint, inside, there is a capsule component, and inside, a mesh component (the one created by default from Character inheritance)
You can select the root and set the animation mode, but you can also select the mesh component to do so (it’s the same)
In my case, because of the head blendshape, I set the head mesh on the default mesh, and I add another mesh component, containing the body. So my character have 2 meshes, but sharing the same skeleton
What I wanted to say is, every meshes have her own animation mode, but only the “default” one really drive stuff.
You need to set all meshes in Custom mode if you want to drive the character from a sequence.
Then after play, reset the animation mode to BP driven.
In fact, only the main Mesh (the one displayed in the BP) seems to affect the play, so I kept all other meshes to custom mode and switch the main mode only.