Unfair demand for recovery amount becasue I did not served complete notice period.

I was employed with one pvt ltd company working in ITes domain. Unfortunately because of my father's untimenly demise I had to resign from my position and could not serve entrire notice period but I supported till manager provided his approval for the release. But now company is withodling my release documents and demanding recovery amount in lieu of days not served. My concern is that I should have been told in writtten regarding the amount to be paid before my release by either HR team or Manager, which was not the case. I was of view that it was a compassionate decision by management but they sent legal notice asking for recovery amount which I feel is unjustified as I had done everything possible to help in transition so that company was not affected in any way due to my absence. Further, final decision to release was from management although I requested for early release but had it been made clear that I will have to pay a certain amount I would have made a different call. I am already emotionally and financially drained due to my father's untimely demise due to illness and now the company witholding my release documents affects my employment chances with other companies. I am unable to join any organisation becasue of absence of documents and company is not willing to provide the documents. My only question is how does the company justify the recovery amount as they have not been impacted in any way by my absence but for me this situation has a huge opprtunity cost as it could hinder my career progressesion and have resulted in me being jobless for 3 months now. It is a pardox situation for me now, company won't budge until amount is paid while I can not pay the amount until I find a suitable job and earn enough money. It was more of a emotional decision from my end but did not expected such heartless actions from company