2 of 2 No blank space goes before a colon (:) or a question mark (?). The word "I" is always spelled in upper case. Also added quote boxes by using ">" symbol.

is it a rule to put “at” after “in”?

I am new to English language. I have seen many times when the word "in" is used to explain an area "at" is also used following it.

For example:

I am living in Tokyo at Koganey.
He is staying in Sydney at Camden.

I want to know that why it can not be written as:

I am living in Tokyo in Koganey.

Is there a rule to follow when writing like this?

I would be grateful if you could give a clear explanation about this.