Your comment: "Sir i want to send all these fields to the mail, i know i didn't use the other fields except username, email and body but i want to use and send the other fields too and i'm not able to do so, this is why i'm here. Please if you can help me with that?"
This implies very strongly that you've no clue what you have - it was cut/pasted from somewhere. I will, however, give you a link so you can learn exactly how to do what you want to do:
HTML Forms[
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If you want work done for you (and since you refer to "your company", so you're being paid for this work - realize that we do this for money, too. If we do you're work for you then we would expect to be paid for it (just like you).