I have had an account with ttn where I already registered a gateway and everything was fine.
Then I followed some Arduino tutorial for mkr wan 1310 and there an account was created automatically with an email registered with Arduino itself.
So, I thought of deleting the first account and register the same gateway as my device is registered with to avoid confusion. So I think that is not possible.
My gateway id is B827EBFFFF15C80D
Thanks for your help