How to Reactivate RDS TS in Win Server 2008 R2

Good Day,

I had installed Citrix XenApp on Windows Server 2008 R2 Stnd. I formatted the Server with fresh Win server 2008 R2 Stnd: and activate it with existing licences.

1: I have installed XenpApp and activate it. 

2: When i tried to activate CALS with License IDs then i got message   "It is already Activated" problem is that i did not deactivate first when i was going to format. i should had to deactivate but forgot.

Is there any way to reactivate the CALs or deactivate and active ????

Regards,

I.A.H