Can't get to channel 3 on my TV

I accidentally locked myself off of channels 2, 3, and 4. So, I cannot get any cable, in my bedroom. I have a Sharp TV. I can't get the TV remote to work to change to AV1 or AV 2, either. Is there any way you can help me, remotely? The installer had to do things a little differently. And, I have no idea, what he did. (Wasn't watching him, at the time). He gave me his business card, but it got thrown away. So, now I don't have his contact info. Please, help me! Is there a way you can relay this message to him. I'm frustrated!  Thank you, Diane