@zainikhan Thanks for your interest. Already solved, thanks to David-TP's tip (see above).

@dpartonginno Thank you once again - the instructions were very helpful. However, none of those changes fixed the problem and I have now even rebooted the network, but without success. I have...

@dpartonginno Thank you for the suggestion. I have looked for references of managing "private" and "fixed" addresses on the settings for the iPa and the Android phone, also on the Deco app, without...

@ARGamingPK1 That is what I am expecting, but the Android app refuses to connect to the Decos, even 'tho it is logged on to that wifi network.

Having rebuilt my mesh network using an E4 hard wired into a Huawei modem, I want to access the network using the Deco app on my Samsung A15 phone, which has the latest Deco (Android) app version...

@David-TP David. Finally, it works! Changing the APN Protocol to IPv4 made all the difference. Thank you ever so much. Regards Martin