Salary been denied for no reason

I had been working in a company as a web Developer for past 1 year and 1 month. Around sept 2020 i asked for uprisal and company denied due to corona but we had ample amount of work daily still they denied my upsial. Mean while i got a better offer and I applied for resignation and they accepted it with a 60days notice. (Here comes the point i was not manager nor i was a senior in office still they needed a 60days notice. So here you can understand my value in the company). So i started negotiating with the company regarding notice period reduction and we came to a deal of 30 + 15 that means 30days full time work then they will relieve me from company and later i have work for 120 Hour that is equalant to 15 days which i used to work after my new office hours almost 7-12 evening and even Saturday to coverup my additional 15 days. So i completely 30 days and i was relieved from the company all management wishes me the best even the founder wished me(I have the proof). I joined the new company and simultaneously working at evening for them. After almost after 2 days management tone chnages speaking bit rude, he started saying work is going slow, and i am later at evening about 10-15min... Note: even when we where working from office 10-20Min are allowed and we used to manage the late min. I feel frustrated i used to all whatsapp status related to 'dont show me your attitude and some job changing quotes in my status. I never specified in whatsapp status that it was for him. After 5 days he removed my access to work my login and password. So when i logged in at evening he i said the login is not working. I said my boss he said wait for sometime. I felt very bad that after working for more than a year he didnt turst me and as a codeing guy and web developer i need a clear mind to work. Working in a untrsted environment will neither work out for our profession or it would be productive for work. Later the same day we had a lot of conversation on whatsapp in which this people said i didnt serve 60days... Basic issue of this matter was I had only 15 days but they had work for me for more than 90 days. Finally both the owner left the group and i didnt work said to take the conversation on mail and that was done this happened arround 18ofsep. And now when i asked the salary this month they said i went against their rule of notice period and unwanted chat. Note: there no valgure conversion made by me on Whatsapp. And now they have stopped replying mail and chat for Last 2 days. Almost they have to pay me 40k. My question was why didn't they inform the very next day that they will not provide me salary. After i asked salary they are telling me they will not pay. Did i do anything wrong? Let me know what should be done... I am also looking for lawyer. So please give me best suggestion