Putting device on its support and Error -106

Hi,

I bought eufy 2k vidéo doorbell + homebase2.
Following the instructions, m’y device seems ok, its connected to thé base and i Can manage it info thé Android app BUT as soon as i put in on its support , i Heard i Guess 2/3 bips and m’y eufy IS not connected anymore…i dont understand, doorbell IS juste behind thé door. I have to redo thé whole process again…it works if i dont put it on its external support…
…thanks for help