pinctrl-single 44e10800.pinmux: could not request pin 28 (44e10870.0) from group EBB_GPIO_Example o

[bianchi]

Everyone,

I have made it until the overlay loaded,
but it's not doing the job properly,
It's not changing the pinmux as instructed, what do I miss here ? What information do you need ?
=======
root@beaglebone:/lib/firmware# dmesg | grep EBB
[23193.563453] bone_capemgr bone_capemgr: part_number 'EBB-GPIO-Example.dtbo', version 'N/A'
[23193.563558] bone_capemgr bone_capemgr: slot #5: 'Override Board Name,00A0,Override Manuf,EBB-GPIO-Example'
[23193.604675] pinctrl-single 44e10800.pinmux: could not request pin 28 (44e10870.0) from group EBB_GPIO_Example  on device pinctrl-single
[23193.716995] pinctrl-single 44e10800.pinmux: could not request pin 28 (44e10870.0) from group EBB_GPIO_Example  on device pinctrl-single
[23193.746768] bone_capemgr bone_capemgr: slot #5: dtbo 'EBB-GPIO-Example-00A0.dtbo' loaded; overlay id #1
root@beaglebone:/lib/firmware#
=======

Thanks in advance for the clue