Company marked reason for separation as absconding - had resigned with written letter

Hi, I had resigned my job three months before with officially written letter to concerned authorities. also explained my situation (family problems) to relieve immediately and same accepted by all. but now received a letter from hr dept as unauthorised absence and reason for separation is absconding. i ad written explanation letter to hr dept but no response from anyone. pf & gf is also pending. kindly advise on this regard and how to proceed further.

Dear Ubaid,
Hi. If you have written approval from your HODs & HR department for acceptance of your resignation then its ok. I think you have not served notice period.
As per my advice you should personally meet your HR head and again clear your situation. Don't worry be polite and take your dues smartly.