I acquired 5 DA14531 BLE modules, I have an issue with 3 off them not programming at all. They seem to be "bricked" as the JLink interface doesn't seem to be able to connect with them.
When flashing with the Dialog SmartBond Flash programmer (v220.127.116.1172), I get the error "No known chip found while opening JLink connection. Terminating process..."
The other 2 BLE modules work fine as is. All the modules are installed on custom PCBs within the same batch. I am at a loss with what to do next, do you have any recommendations to try?
Attached are the programming errors I experience via both SW and UART.