Is the PAN of your partnership firm still active?
If yes then you can claim refund by requesting a condonation and filing Nil return and claiming refund.
I don't think government department will make such a mistake and deduct TDS in 2016-17 on transaction undertaken in 2015.
The amount on which TDS was deducted was shown as income in 2014-15?
You can still rectify your return for FY 2014-15 before March 2019 and claim TDS deducted and claim refund.
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