I literally have an instruction manual in-front of me as I have an issue with mine too at the moment, Stopped working after I changed the battery's as the safety edge and control unit seem to have lost the pairing and I cannot repair them (light on the safety edge will not come on when pushing the pair button).
I am hoping my issue is that I put in some cheaper battery's from ebay that are 2700mah instead of the 2600mah, Although its the same battery's I took out I know they are not the original ones which are these that come with the safety edge in the original box:
https://www.ebay.co.uk/itm/17492508...rentrq:7e653dd017c0ab96a36ea202fff34aea|iid:1
Sounds like you have a different issue though as 2 beeps indicate a motor problem.
I'm getting 5 beeps for safety edge issues. Door works up fine but I have to hold to run (deadman mode) it to come down.
As RandonGrinch said batteries should be 3.6v not 5v!
Update!
I just went to have another little look at my door pushed the safety edge button, Light flashed, Connected and all works fine again! Totally random as I have been playing with it all week on and off!
I wonder if the 2700mah batteries I put in were a touch too powerful and with a few days being fitted they have drained a little and are now detected, Weird!
Anyway good luck with your issue but 2 beeps is motor related, Door should always still go up normally with just a safety edge issue as that only come into effect with closing.
If you open your control unit a led 2 is the only one flashing you know that is paired to you control unit and should be working.
Do make a note of the codes on your control box and safety edge as the Teleco N09 does have a few variations over the years with different codes and slight variations in the instructions.
Might be worth trying the turn off/ dip switch method to deactivate you safety edge completely. That should help to narrow down motor or safety edge issues.