Welcome to the forum
Sorry that your slide is stuck, What beeper is going off. I had a 2003 Bounder on a Workhorse and it had 2 slides but no beeper- alarm. Do you have the jacks still down? Is the key in the on position? Parking brake? Drivers seat all the way forward, sometimes there is a kill switch on the seats. Hopefully you will gets lotsa great responses.
Good Luck...Keep us updated...Peace...D