How do I claim TCS refund on money received as gift

Hi all, 

I'm an NRI permanently settled outside India and my mother is a permanent resident of India. I recently received some money as a gift from my mother from her savings account into my NRO account. Since this was a transaction under LRS a TCS of 5% was applicable (nothing was deducted at the time of transaction but the bank said it will be deducted from my mother's bank account). 

Now I understand that the TCS can be claimed back by filing an ITR. My question is, in the above case who needs to file the ITR to receive this TCS. Is it me or my mother? 

Thanks in advance.