looking at your channel i can see why they unpartnered you. you do not own the rights of the videos you have uploaded. Your channel represents a liability for any youtube network at the moment. You can say that the users uploading must have rights to do so but that does not work like that. for every single video uploaded you need to have authorization from the original or at least you need to know what kind of authorization the video falls in, creative commons, open domain and so on. It is your responsibility to follow these rules, despite you not having any strikes yet is pure luck. If you own the right of the videos then you need to show some proof