Chosen Solution

I used to have a polaroid 600 and it never let me down, last week I bought a new polaroid on ebay, the one step sx-70 rainbow and I was just waiting for the film to arrive so I could start taking pictures, I took my first one last night with flash and then I went to bed, so when I woke up my photo would be ready. I kept it in the dark and the temperature wasn’t too hot and it wasn’t too cold either, the conditions to the development was completely right. Then when I woke up(after 6-7 hours) my photo was still all black!!!! I’ve never seen that happen!!! And now I don’t know if the problem is the camera or the film( impossible project) all I know is that I wasted 4 dollars in a picture that it didn’t develop!!! Is there any way that I can make it develop(even though 7 hours is great time to the full development)? Is my camera damaged ? Because it really looks like new but after this I don’t know Help me I don’t know what to do!!!!!

the shutter isn’t opening, I have the exact same problem, with the exact same camera. I don’t have a fix for it yet, just try talking to camera repair people to see if they know anything about the disassembly of the model