Why can I NOT create multi-room group using SongPal??!

SRS-X77 Speaker & STR-DN1050 Amplifier - Both Multi-Room/ SongPal Link compatible -

but on the app- the create group button is blanked out.

Have tried everything: 1) update firmware 2) update SongPal app, 3) disconnect all devices from Bluetooth, 4) reconfigure device wifi settings  etc etc... Still the same.

Then....Tried calling Sony -twice, emailed once, was promised a return call. Still no response from them 3 days later! Might as well return the SRS-X77 for a refund, and give up on the idea of Sony MultiRoom!

Unless someone here can help?   Many thanks....:)