Hi,
Have a read here and provide hardware details about your device.
Have you tried v4.30?
The issue you describe could be DFU compatibility issue or device license.
I recommend you try Benf 3.64 V3 firmware which works on new DFU V3.45D. The patch was done by rimidalv007 here and I fixed minor hex bug.
BenF_3.64APP_3.53LIB_patched_v3.zip (48.9 KB)