nRF52 doest boot after programming

[mojangeex]

Hello, i am experiencing a new issue that wasnt present before. 

After I program a device, board does not boot right away, but i need to do a power cycle in order for the device to start advertising. Device also doesnt go to any DfuTarg mode or anything like that. Normally wouldnt be an issue during fabrication, but it also happens when I do the buttonless DFU. Due to device being packaged with a battery its not an option to remove it in the field. 
I am using nRF sdk 17.1 and secure bootloader. 
Any recommendations where to look for problem would be helpful.

Best regards

[mojangeex]

Update, i found the issue
Due to accelerometer on my board already being programmed, after flashing nRF52 accel had set int pin to high. During bootup interrupt handler is called before spi init and device in interrupt tries to do spi write without spi init being finished and even watchdog being set up so it just hangs there.