Tried Hikvision firmware does not work, bricks Annke I51DX.
Here's the latest Annke firmware for I51DW/I51DX. https://download.annke.com/firmware/I51DW/5.7.10_240426/digicap.dav
I was able to unbrick my I51DX with this firmware.
the Annke I51DX and I51DW uses that same firmware.