Thank you very much for your question and your interest in the TMHV.
Could you check in the performance monitor on this hyper-v host? Task Manager is receiving this data from
CPU: "Hyper-V Hypervisor Virtual Processor" > "% Total Run Time"
Memory: "Hyper-V Dynamic Memory VM" > "Physical Memory"
There could be duplicates if you for example renamed a couple of VMs and "switched" their names and didn't restart these VMs. Try to restart the Virtual Machine, this will update the instance name in the performance monitor. In case onf renaming issue - restart also a VM that has be renamed to the other name.
I have seen this before and when Sergey's tasks don't work, it probably means there are double references in the WMI database which is not cool. My advice here would be to get support from Microsoft in order to solve this.