Is it a Schlage connect lock zwave plus signal strength issue or aeotec issue?

Tried to connect my Schlage Connect lock with aeotec hub, the two devices could be connected together successfully, but only within very very small distances, less than 6 inches. Any distance beyond, the connection will lost.
Any idea what the issue could be? Any solution?

If its the pre ZWave plus version of the lock this is intended behavior. It exchanges the S0 key with your coordinator (the hub) in whisper mode to prevent someone else intercepting it.

Later versions of the spec go with much better methods tk secure the key exchange

My two Pre-zwave plus Connects require the coordinator to be almost literally on top of the lock to successfully pair or exclude, but my recently replaced ZWave Plus S2 capable version happily joins across the house.

Thanks for the info. The problem I’m facing is what to do after they are paired, when I move my hub away, then it just lost connection with the lock.

You may need a beaming repeater close to the lock. See the following FAQ:

FAQ: why would I need another beaming repeater if my zwave lock is already close to my hub?

Bought a AeoTec range extender 7, paired successfully. But kind of falling into same issue, as long as the extender is very close to the lock, everything works fine, but I can’t move it away. My nearest outlet is 7 feet away from the door lock.
Any other suggestion? Is that ZWave plus such bad? or is it just my Schlage lock’s defect?