Termination because of dual employment - joined another company B without resigning from Company A

I was working in company A since July 2021. In January 2022, I joined another company B without resigning from Company A because I was admitted to the hospital. After recovering, I resigned from company B. Now, Company A found that I was working in another organization for a month with help of a UAN number. HR called me and said it is a breach of agreement and they are going to terminate me. They will issue a show-cause notice soon. HR said that He can help by not taking any legal action against me. He also said that he will make sure that no remark will be mentioned in the case of BGV from another organization (no guarantee). I know what I did is wrong.
Please suggest what I can do now?

The motive of HR person in the help offer is suspicious. Probably at this point you have no other option but to go alongwith him. Accepting double employment is a very serious issue and there is no other punishment other than termination of service. Your very credibility as a person with integrity is now under question and the reason you give is far from credulous.

Hello Team,

As i am looking help on preparing termination letter for dual employment, without pay.

What suggestion can any of us give you?
You know the company and the details, we don't.
You know the nature of the people, we don't.

There are discpreancies in your post, which also you alone will know the details.

So, basically, you joined a company without resigning from another.
But you claim to be in the hospital and therefore didn't actually work for either during that period.
So to me it seems to be just a paper-work discrepancy. but if the HR is insisting on terminating you, there must be other thing you have not shared. Did you actually work with both companies?

In any case, if employer wants you out, there is very little you can do, because he will find multiple way to remove you. So you may as well move on. I really do not know what suggestions you were expecting from the forum