Issue: "The previous activation key has not been accepted by the license server."

I copied and pasted the updated license for DP 16 from the dashboard, then it asked me to fill in the license for the previous version, I copied the license for DP 15 again, then I was prompted for this: "The previous activation key has not been accepted by the license server.".
Any help would be appreciated!
PS. I am activating on two computers, but will not use both at the same time, is this allowed?

 

Hello, could you provide us with your license key via the private message please?

 

Could you please tell me where can I send you a private message?

 

Hello?

 

I've just sent you a pm, please check your inbox and reply.

 

I have the similar issue. @Maria@Parallels , could you help with this issue?
Thanks

 

Hi, could you provide us with your license key please?

 

I also have the similar issue, I tried to upgrade from Parallels 16 to 17.
Can you help me with this? @Maria@Parallels.

 

Hi @Maria@Parallels - I am in the same boat. How do I send you my license key?

 

Hi, we have sent you a private message. Please reply over there.

 

Hello @JunkaiC, we have replied you via the private message. Please replay us back.

 

same here. pls help.

 

Hi, please provide us detailed information of the issue you are facing to assist you further.

 

It asked me to provide the previous key, but after given it prompted: "The previous activation key has not been accepted by the license server.".

 

Hi, we have sent you a private message. Kindly help us with the both license keys over there.