I'm running vRA 6.2.1 and also experienced this issue. Confirmed resolved by the earlier suggestion to change from UK regional to:
Control Panel > Region and Language:
Format: English (United States)
Location: United States
Administrative > Language for non-Unicode programs: English (United States)
I didn't need to make any changes to the web browser (Chrome) being used on the workstation requesting the changes to the VM.
same issue in the UK with 6.2.1
is this fixed in 6.2.2 or any other version? guess it saves me from having approvals for reconfiguration as nobody can allocate themselves more resources!