How to merge two domains/products for a same email address

[Thomas LUK]

Hi everyone, I don't know why there are two domains for the same email address. (see attached image)

These two accounts or should I say products are completely isolated. My question is why does this happen and how can I merge them back into one?

Thanks 

[Bill Bailey]

Looks like you set up two different domains, maybe signed up twice? You could delete one and focus on the other. But there is no way I know that you can merge the two together (except manually).