My employer refuses to give me experience letter

Hi all, I was on leave on the occasion of Durga Puja which was intimated to the HR and the CEO of the company verbally. The leave application portal was not accepting leave hence i was asked to apply leave in backdate. On this course of vacation, existing colleagues started a rumour that I am leaving or absconding the job due to which the CEO seized all my email credentials and expelled me from the company group. On the same day they sent me an SO CAUS notice after which I visited the company premises and had a word with the CEO and he charged me of instigating other employees to leave the job which infact in real the incident is the emplyee wanted to change and thats when i referred them to other organisations for which I have digital proof. Now the CEO terminated me and has put my previous month salary on hold and asked me to resign and can take the salary provided they will not issue the offer letter. I have worked for this company for 1 year and 10 months and was among the top management employee with good performance rate.