This subscripton is using all 10 Total Regional Cores availabl !!

Dears, 

I am facing a problem that I have an Azure subscription (Azure in Open) 

I create 2 VMs with total 10 Cores on West Europe region when I try to add any machine in same region that's appear to me

" This subscription is at capacity for Total Regional Cores on this location. This subscripton is using all 10 Total Regional Cores available." 

and all my work must still in this region in order to the net latency 

I don't know where is the problem and how can i Solve it 

Thanks for your help