Will not start after replacing timing belt

I have replaced the timing belt. When I took the belt off I didn’t see the timing marks on any of the gears/sprockets (not sure on which they are named) move out of place. I put the new belt on and all the timing marks are lined up and everything. But when I try to start the car it doesn’t start just sounds like it is turning fast or something. The timing belt also turns when trying to start it if that’s any help. I have looked all over the internet for solutions. Some say the timing could be off 180 degrees I have tried that to see if that was the problem to no avail. I also checked if number one piston is in TDC and made sure the timing marks were aligned also to no avail. I have tried everything I could think of and everything that made sense from different forums on the internet. I don’t know what the problem is I’m lost. I could really use some help on this. Thanks in advance.