REFUND OF EXCESS TDS AMOUNT DEPOSITED BY MISTAKE

Can Somebody help me about how the excess tds challan deposited by mistake by  the deductor can be refunded. I have already filled form 26B online and also submitted the acknowledgement with all the supporting documents to the income tax office. It has been 1 month but still on portal it is showing "Pending with AO TDS". Can somebody help about how much time it normally takes for the process or whether I am missing any step which needs to be performed. 
Thank You