Offer Letter received and resigned from old company but could not Join new company due to COVID 19 Lockdown

Dear Seniors, On getting company offer letter, I resigned my current job but due to lock down new company not able to join ,I am jobless because of there offer from 2 months ,how to write a mail to new company to give me 3 month salary as compensation because I exit my current job due to there offer of employment.

New company is not bound to give you 3 months salary as compensation.
Contact new company and explain the current position and seek additional time for you to join.

I afraid you have not taken adequate steps in time to safe guards against adversaries (issues). In the first place you should have requested them to grant sufficient joining time quoting COVID-19 lockdown/inability to travel etc. You have not mentioned whether really attempted/taken efforts to travel to the co and tried to report (and saw yourself the co also under lockdown). If this has happened you can have better chances. Nevertheless you should not wait anymore/delay, go there and report and see what happens. There is no point in dragging the issue further.

Sir,
I have discussed many times with HR and also with my reporting manager even I also write mail to them asking for joining date but they didn't reply ,on discussion they confirmed that joining decision pending with management. Now offices are open but still they not confirmed.

In the circumstances, why don't you visit them and find out exactly what's in store for you. This might give exact status. I hope the co also in Chandigarh. If the co. is outside travel permit/pass might help you to go & reach them. Try it out. Take proactive steps so that you'll have clear position.

Sir ,they ask me to absorb with your old organisation as current financial situation of the company not good ,So I want that they give me 3 month salary as compensation ,can I write mail to them asking for compensation

All companies are under financial stress due to lock down. Even during normal circumstances companies try their best to avoid payments to employees who leave. Hence expecting payment of three months is almost impractical. You have to grin and bear for some time till situations improve. All the best.