Replaced iPhone 3GS's Digitizer and Frame, now white screen?

I have a white iPhone 3GS, as you probably know the white version only comes with a white back, and the screen is still black, so I decided to buy a new digitizer off ebay to make my phone completely white.

The repair was successful, my phone worked, but I realised my screen was at a slight angle because I didn't place it in probably, so I turned my phone off, got the suction cup, and took off the screen, I tugged a little to hard to the cables came out too, so I put them back in and re-positioned the screen.

I then pressed the power button, and nothing happened, but it was turning on, when it finishes booting up a white screen appears, I can toggle this on and off by pressing the lock button.

My phone shows no image when booting up, doesn't even turn on, just stays off until it's completely loaded.

The phone still works, I can use voice control, and I can still power off, etc, but I just can't see anything on the screen.

I have tried plugging in the screen again and the cables are in fine, the digitizer still works because I can hear the sound it makes when I press on it to enter my passcode.

I have also tried holding the home and lock button at the same time, but my finger keeps slipping after a few minutes, but I don't think that would solve the issue.

What are your suggestions?

Those LCD screens can be a bit fragile, possible it was damaged when you pressed the screen in when it was not fully aligned? Bad connection, damaged cable, etc seems like you already checked those. Hard reset can sometimes work but in this case, likely not the solution. Replacing the screen may be the next best thing. But I would check connection and cable for rips a final time before resorting to that.