@Radu_C Have you noticed on which wireless channel the connection with your hotspot was established ? You may take a look at this thread for more details on you issue.

@GPBH What you can try is a hardware reset by pressing its reset button for about 10 seconds. If the RE190 works after a successful reset you have to re-configure it from scratch. If it still behaves...

@mautoza Are you using your new router in AP mode (access point mode). If that's the case there's no advanced tab in its WebGUI: In this case following the guide you mentioned all setting should be...

@GPBH It depends how old is your device - if it's under warranty contact your retailer, otherwise contact your local support for assistance.

@Rajasekar If you use a DSL modem, probably this video guide could help you to resolve your issue.

@SharkAttackRJ If you have an ISP modem router before AX90, you probably are behind a double NAT. If you want to avoid that you may refer to this guide (in case ISP modem router allows bridge mode)....