nRF52832 advertising not picked up by certain Androids

[danimalia]

Works on Huawei P20 Lite (Android v9), Samsung J3 (Android v7.1.1), all IOS phones.
Doesn't work on Samsung A50.

Samsung A50 does see the devkit when using the same firmware., could this be hardware related? (custom PCB)

[danimalia]

note - verified on two separate A50s. Have also rebooted in safe mode, and removed all BLE apps. phone still does not detect this nRF.