upgrade precheck fail and /cyc_cfs 100% full after running cleaning script

Hi dears, 

i have a powerstore 1000T and it's running 1.0.2.0.5.003 os version 

i'm trying to upgrade the OS to the 2.0.1.3 but the health check is failing in the prestage step at 5%  with the error message :"The system encountered unexpected backend errors. please contact support (0xE04030010001) "

i checkd the system space usage at the (/) partition using the command df -h and it's showing that usage of 16% 

but i noticed that /cyc_cfs partition is at 100% of usage

i checked further /cyc_cfs/service/telemetry_backup and i found that it still have old service data, config data and system dumps but i'm not able to delete them.

i've run the svc_cleanup script several times with different options but with no luck 

i've tried the svc_dc delete command but same thing no luck

i found an article https://www.dell.com/support/kbdoc/fr-tn/000182353/powerstore-support-materials-send-to-support-failing-post-upgrade-to talking about rebooting control path (cp) but i didn't exactly understand what they mean by that.

i've already rebooted the tow nodes one by one but still having the same problems 

i cannot open a ticket with dell support because support contract is expired and i hope anyone can help me with this issue.

best regards 

Aymen KHELIFI