Hello!
This sentence is not correct. I could give you tips on it though.

First of all, some of the wording does not make sense. For example, 'I will call u once i reached office',
is not written correctly. You can revise that by writing:
I will call
you once
I have reached
the office.
Also, punctuation and correct sentence writing is a factor. Instead of writing,
'I am traveling, it is noisy here, i cant hear you, i will call you once i have reached office.'
You could write, ' I am traveling
right now and it is very noisy
. I
can not hear you. I will call
you backonce I
have reached
the office.'
This shows the person you are dong something right then and there but you appreciate their call and you would
definitely call them back.
I hope this helps you.

Keep trying to grasp the English language. You'll get it!
Ayumi Yoshikawa