does not accept PHY update from connected device, does not log it

[fanoush]

Describe the bug
There is a menu item to set preferred PHY on connection. This works, I can switch connection to nrf52840 device to CODED and back to 2M or whatever. My device gets the PHY update request and handles it by default code in nrf5 SDK and it works. I can see in nrfconnect log the phy being updated and also when selecting 'read PHY' menu item it shows again correctly in the log (both TX/RX as CODED or 2M)

However it does not work for the other direction, my device sends PHY update request to CODED back to the phone and nothing happens at all - nothing in log and the phy remains the same.
In the device I send the BLE_GAP_EVT_PHY_UPDATE_REQUEST with phy being CODED=4 and I later get BLE_GAP_EVT_PHY_UPDATE event with success status code 0 and RX/TX phy being unchanged and still 2M=2

Expected behavior
central device = phone running nRFConnect should accept PHY update to CODED
nrfConnect should also log the device PHY update request with the result (changed or unchanged)

• Android version: 12
• Phone model Motorola Edge 30 (dubai)
• App Version 4.29.1

Additional context
this is tested with nrf52840 boards running Espruino
PHY update works in both directions (central<->peripheral) between two devices running Espruino so I don't think the device is the problem

[fanoush]

Actually, it did not work for me several times, but I tested it today again repeatedly and sometimes it does work! here is screenshot and below code run on the device. First I switched PHY from phone to coded,1M and 2M, all worked And I got phy change events. Then I tried to updated phy from device to coded and it worked!! But then I tried to update again to 1mbps and it stayed at coded, then to "auto" twice and nothing, but then to 1mbps and then to 2mbps and both worked. Then to coded, 1mbps, coded, coded and didn't work again. From phone it does work everytime.

>NRF.on('phy', function(phy) {print("PHY=",phy) });
=undefined
PHY= [ 4, 4, 0 ]
PHY= [ 1, 1, 0 ]
PHY= [ 2, 2, 0 ]
>NRF.updateConnection({"phy":"coded"})
=undefined
PHY= [ 4, 4, 0 ]
>NRF.updateConnection({"phy":"1mbps"})
=undefined
PHY= [ 4, 4, 42 ]
>NRF.updateConnection({"phy":"auto"})
=undefined
PHY= [ 4, 4, 0 ]
PHY= [ 4, 4, 0 ]
>NRF.updateConnection({"phy":"auto"})
=undefined
PHY= [ 4, 4, 0 ]
>NRF.updateConnection({"phy":"1mbps"})
=undefined
PHY= [ 1, 1, 0 ]
>NRF.updateConnection({"phy":"2mbps"})
Uncaught Error: ERR 0x11 (BUSY) (:4183)
    at REPL (:1:37)
NRF.updateConnection({"phy":"2mbps"})
                                    ^
PHY= [ 2, 2, 0 ]
>NRF.updateConnection({"phy":"coded"})
=undefined
PHY= [ 2, 2, 0 ]
>NRF.updateConnection({"phy":"coded"})
=undefined
PHY= [ 2, 2, 0 ]
>NRF.updateConnection({"phy":"1mbps"})
=undefined
PHY= [ 2, 2, 0 ]
>NRF.updateConnection({"phy":"coded"})
=undefined
PHY= [ 2, 2, 0 ]
PHY= [ 2, 2, 0 ]
>NRF.updateConnection({"phy":"coded"})
=undefined
PHY= [ 2, 2, 0 ]
>

EDIT: so to sum it up - mostly it doesn't work and nothing happens on phone side but sometimes there are brief periods where it does work.