Hello Kim,
1. possibilities are: a foreign object is probably in the opening of the doors path. ( you might have to open the player to see this)
2. Gears for the door are either damaged/broken (since they are made from plastic) or mis-aligned. Sometimes when DVD/CD players are forcefully pushed in/open it tends to make things abruptly operate.
3. Try recycling your power by unplugging it from you power source and waiting about a minute or two before plugging it back in.
Hope this helps you.
Have a nice day as well.
Tony
December 2006