My Nireeka Prime pedal asistent stopped working.

Hello!dear Nireka team.
I have bought in 2022 the Nirkea Prime whit 1500w motor whit all of the extras of the best.
I live in Germany.
Now after 2 years i need your help ,because i have this problem whit the pedal asistent, its not working anymore.. The gass function is working but i prefer the padal asistent to work because whit out it, my battery is discharging faster.
One day it was started working again about 10 minutes.
What can i check on the bike maybe i need to change a cable or something else what do you saggest what can i do to resolve this problem?
Maybe you have some video on YouTube or some pictures to sow me where to look for the problem and what to try.
I look for the magnet but its okay i think.
Please help me.
Thank you!