I installed the Espruino firmware to my RuuviTag for some quick testing and after I was done I wanted to update the my firmware back to the latest Ruuvi firmware. I followed the instructions (https://lab.ruuvi.com/dfu/) and did as instructed. My tag was seen with the name “DfuTarg” as I started the DFU-update process with NRF-connect and as soon as it started I got a disconnected notification and the DFU-update stopped at 0 %. I tried it a few times again and also with different phones and the result was the same. Does Espruino firmware prevent the DFU-update or am I just doing something wrong here?