Is this correct?
They already replied me and I have attached that email here. I replied them back but they still did not reply me back again.

Question

Is this correct?
They already replied me and I have attached that email here. I replied them back  but they still did not reply me back again.

Answer

They already replied to my message and (see attachment). I wrote them again but they have not answered me yet.

Answer

(This will sound more natural and native) "They already responded and I have that email attached here, but after I replied back they never got back with me."

**This is a lot more natural sounding because it is fairly straightforward and I would say more American sounding. Heinz's answer is correct, but it sounds a bit too proper, if you know what I mean.

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