HELP! Weird Diagonal Lines in half clip

Good afternoon!

I am working on a project from quite a while ago, I am trying to update and spruce it up. It is from about a year ago so I am sure the version of premier was different. When I open the project it has me convert it to the new updated premier that I have currently. When I look on the timeline, the clips are all still there but half of them have these diagonal lines through them. The clip plays fine up until the lines, the it is just black video and will not continue playing. I opened other projects from the exact same day that I created a year ago and all of those clips in all other projects are fine. It almost cuts the clips in half...I tried to open an older version of premier to try and read them, I tried copying the clips to a new file and re-importing them into a brand new project and it would only import the clips up until those diagonal lines start, so I am only getting half of the clips. I attached a picture to show you what it looks like. Please help!