Task ended failure without any results gvm version 20.8 on debian

Dear support team

i have excited to test this tools and compare its performaces in my Debian Os
i have installed GVM assistance 20.8 so i have insalled and updated all libs and NVTs, feets updated,etc but when i created and ran a task and select any scanner always all tasks say interrupted and ended 0% percent without results.

result task:
scan process failure.
Task interrupted unexpectedly

i dont know what else to do to resolve this issue.

i have checked this 4 logs in path /opt/gvm/var/log/gvm
present this:
gsad main:WARNING:2020-11-26 16h35.52 UTC:484: MHD: Error: received handshake message out of context.

show this:
INFO: (ospd.ospd) 6a633c13-6430-4932-b8a3-15956cbea33a: Scan stopped with errors.

show this:
lib nvticache:MESSAGE:2020-11-26 16h28.45 utc:52741: Updated NVT cache from version 202011191132 to 202011260907.