Not Getting my experience letter from the company

Hi, I have been working with the company for 15monts. Here are the offer letter points Termination points (for reference): 1.Termination of employment by either party shall be Three months’ notice in writing or payment in lieu of notice. Such notice may not be offset by unused leave. 2.If your actions at any time constitute a serious breach of ******(company Name) standards of behavior, ****** may end this contract and terminate your employment immediately. 3. This appointment letter is issued on the understanding that all the information given by you in the application / employee data form / during the interview or data provided prior to and / or at the time of joining is true. If it is found at any time that the information given by you is not correct or true or you have knowingly suppressed any information, the company will have the right to terminate your appointment with us any time without any compensation. I have resigned from organization after 1year and resignation is accepted with approval mail. I have asked them for the 1month or 2month of pay in lieu as per the offer letter, but the Director didn't agreed and gave threat that you go to court and get if you want. I didn't do anything like this and started working on items given. Later, I started serving notice period, and in that phase I been harassed by the Director and gave burden of work, I still worked on the items. Also for getting 2-3 days leaves which are pending, and due to urgency they didn't approved instead put pressure and approved at later stage. But due to urgency I need to take leave one day prior from the approved leave dates. After coming back from leave they started more harassment, torture using abusive words on me. Even at the same time they threat they will terminate and will not give salary or anything to me. Due to this continuous harassment and torture, I am feeling physically and mentally stress and not able to work and live properly. Before my 10days notice period left, they provided me 2options, a)To serve notice period more 2months and complete work, b) Go now, and without any salary will give you experience letter. Else will terminate you, and after 3months notice also, we may not give you all documents and you want to go to court then go. So, I choose (b) I will like to leave and will take my experience letter without salary. So, I have drop them last working day last mail and left. Later, they send a Termination mail to me reason being, I didnt produce work in notice period and didnt gave my 100% - (As proof I have sent them mail that I am not productive to 100% as I didnt get hike and not reveling me early in notice period.). Also, another reason saying I lied to them on taking leave and travelling before the date I said them. - (I agreed to them I travel early anc cant produce ticket for the date mention in mail.) and later with Termination mail, they gave salary. I have following queries. 1. Can you tell me what I need to do, to get my experience letter from the company? 2. Can they terminate me after my resignation even after serving my notice period for 2.5months and have left office before 10days of completion of notice period, on their saying.?