You're welcome! Actually it was somebody from TP-Link Nederlands who gived me the solution.

@David-TP I will help you a little bit later submitting... no problem

Yes... I solved the problem, the app is not compatible with my phone, I used my tablet and now it's working. Thank you.

Hi. I've bought a Deco X20 AX1800 superior mesh wi-fi 6 system, I've watched some tutorials for installing but my phone application is always blocked on the "Looking for Deco..." screen... I really...