Vm346 vtech monitor not connected

Hi

i have my vtech baby monitor model vm346 it was ok just the charge was damaged and loose so nOt charging,, i change that and now its ok

but only today after 2 years of good using of it ,, if i open it i got a message and it cant be connected although the camera is paired .. so everytime i switch off the parent unit then i switch on i should again unpair and pair the baby unit so it will be connected

attached is photo of the message i received