Create an animation from obj/gtlf files, import in Unity

Hi! I have 350 gtlf files. Originally files are in OBJ format (350 files + audio) and I have converted them into separate gtlf with obj2gtlf. How can I create an animated gtlf file with all 350 keyframes? Or how can I create an animation in Unity using these 350 obj/gltf files? I want to import/create a animation in Unity using these files and run a Hololens Application. By placing this animation I want to see a volumetric video playing inside my Hololens Application. But I can not make a sequence using a gtlf-transform, it seems to take only one gtlf file (instead of all 350) and detach the texture into separate jpg-file. I can not create animation with Timeline in Unity. Can anyone help me? I am new to Unity and can not find a solution