I have a BL653 module and with a lot of efforts somehow I was able to successfully create a secondary slot for mcuboot in external flash connected using SPI. Every time I try to DFU over BLE the latest FW image gets loaded in external flash which is secondary slot - slot 1. But I am unable to load the latest FW image in slot-0 or to boot the latest FW from slot-1 itself. I am using nRFDeviceManager app for my experimentation and try to upload the dfu-application.zip from build folder. When I click TEST the RTT shows <err> mcumgr_img_grp: Faled boot_set_next with code 3, for slot 1, with active slot 0 and confirm 0. Also the app reports error Invalid image header magic(23)
Here are the snips from app
Here are the settings from mcuboot.conf file
Here is zip of my build folder
Could anyone guide me on how to boot the image from secondary slot or copy it in primary slot