non refund of deposit

&lt;p&gt;&lt;b&gt;Location/place&lt;/b&gt;: hyderabad&lt;/p&gt;<p><b>Name of company/service</b>: you broadband</p>I have taken you broadbad internet connection 6months ago. now I have relocated to new address and they dont have connectivity there. so I called for cancellation of my connection. they did so. and now they are not returning my deposit amount of 500/-. they are saying it will take 45 working days to send the cheque and its their policy. to establish a connection they need only 1 day and for refund they need 45 working days? what kind of rule is this?
I asked them to collect their modem only after paying me my deposit amount back.
please help me. this seems like a big fraud. how come it will take 45 working days to prepare a cheque? for a new connection, they take maximum 2 days. they dont pay any interest on my 500/- for those 45 working days, which is a big loss to many and a profit for the company.
if they do like this with all the customers, then that itself makes a huge amount as interest.
so I demand my 500/- on the same day when I return the modem, or else, I demand an interest of atleast 4 percent which banks are paying to SB accounts, for those 45 working days.
thank you.