Anet a8, dropping z axis and makes nozzle plow on the bedsurface

Hi folks!
Im new to the forums and 3d printer world.
Got my self a new printer. But run in to problems that I have no Idea what it is.

When doing Anet autolevel sequense. "Custom leveling"
It firs go well. Finding bed hight. But when continuing the sequense. It drops below bedhight
with nasty nozzledragging effects on the bed.

I have put up a clip.made it 4 am. So a bit tired!

[youtu.be]

P.s!
What a awsome forum this is!

Best regards!
Johan, Sweden

I don't run auto level on my A8, but from the problems encountered by those that do I would say that the nozzle is too low with respect to the levelling sensor.

The part in the video where it drops Z after homing X Y, is where the existing bed lvl matrix is catching
up with itself(seen by Z not moving while homing x y)

Try erasing existing matrix from eeprom, then start the auto bed lvl

Ty for the responses!

I have now found out the problem
While calibrating nozzlehight with Zaxis. The firmware does not seem to save the settings.
Lets say I do nozzlehight calibration. And direcktly go back and do another round.
The for example low nozzle hight is the same. After working with this problem for days.
Im pretty frustrated.

Obevan. Any ideas how to erase this from eeprom. I have not found anything how to do this with
stock firmware. Well. Havent played around with any firmware for like 20 years.. lol

Any guidences is very welcome!!

Sorry, dont know the anet firmware,
I use repetier which uses M322 to erase the matrix.but i doubt that will work on your firmware.