Invalid key

Hi ,

i purchased norton 360 multi-device .

it is for 5 Devices .

now i installed on 1 PC ( PC1 ) and 1 mobile .

 

then i register key on other PC . ( PC2 )

 

But interesting , becuase when i register key on PC2 , sudenlly PC1 show error " expired Trial and show invalid key " .

 

When i again active key on PC1 , then PC2 show this error .

 

then We again register key on PC 2 , again PC1 show this error .

 

i can not why any time register key on other PC , other PC show error and key exit from AV .

 

AV = norton 360 premium

 

Thanks ,

Regards ,