143 Visa Documentation with Dependent adult child

[Lucky007]

Hi all ,

I am new to this forum, 

My mother applied 143 visa 2.5 years back and she add me as a dependent child becaus I am doing my post graduation studies .

Now case officer is assigned to her file and we got an email saying that provided documents shows that I am a dependent child .but they want some proff that my mom she pay me money for everything like for my study,food ,trevling and daily  allowance and case officer want to see bank statements that shows that my mom she is transferring me money for everything .

But the place I live in we pay cash for all our transections like groceries , phone boll,water bill ,medical etc .

Now I dont know how to prove that my mom is giving me cash for everything because cash is the only convenient way for us because where I live we don't use EFPOS or debit and credit card for our purchase and bank statement of my mother  account shows that she frequently withdraw money from her bank account and in that bank statement there is no online transection and other direct debit because the place I live in we do 100% transactions in cash and it is true .

Now we just amazad how to prove this truth .

Any sugession is we'll come 

What can we do in this case 

And I am sure there is way to get out of it