Craftsman Opener, Liftmaster Remote PROBLEMS!

raftsman garage opener of MANY years (probably 20). Had no problems. Our remotes (2 of them, one opener) stopped working, replaced batteries and stil didn't work. So, I replaced the remotes with Liftmaster compatible remotes. Reprogrammed the new remotes...The (one) remote worked great first day...even increased our range. The other remote I tried from my house and the door went up (so, I assumed GREAT!).

Today (2nd day)... COMPLETELY, different story. The remotes only worked when I was 4 feet from door. I reprogrammed remotes again and have this problem.... I push the learn button (to reprogram) and all I get is continuous up and down cycle from the door. I couldn't stop it...so I cut the power to the garage. Turned the power back on and ....up and down, up and down. Finally, I hit the remote button a few times to get the door to stop about 3" on the 'up cycle' cycle.

Have no Idea whats going on.
Tried this....
Took batteries out of remote and put them back in.
Can't reprogram them now bc the learn button automatically sends the door into up and down cycle.

HELP!

It appears that the opener is getting a signal from something. Remove all the batteries from both the old and new remotes. Disconnect the wall station (or button). Plug the opener back in. Clear out the receiver memory by holding the program button for 10 seconds. Put a battery back into one of the remotes & try reprogramming it.