Hi, I encountered a similar problem.
Went to https://ipcamtalk.com/pages/hikvision-password-reset-tool/ and got a code (SSrRdyeSzS), but when I used it in the SADP tool it gives the error message "Failed to reset password. Device denied."
Device serial no.: DS-7204HGHI-F10420170724AAWR802830131WCVU
Start time: 2019-02-15 14:10:38
DSP version: V5.0 build 170621
Would really appreciate some help!