I am in a situation where I am serving notice period as I have an offer in hand. But I am trying to find out if I could get some other offers as well.

But the problem that I am facing now is, during the initial discussion with recruiting team I have informed them that I have already accepted for company X with salary Y and looking out again If I could get better opportunity(Reason for sharing this is they are explicitly asking about looking for another offer with an offer already in hand).

After the initial discussion I am not communicated with further details, especially with further technical rounds of interview.This has happened with almost all the companies that has discussed with me. I can say 95% of the discussion has ended up in only one discussion.

I would like to understand what could be happening in my situation? Does the recruiting team does not considers the person who is already having an offer?

Any help in understanding this could be helpful for me. Thanks.

EDIT1 : As mentioned by @Masked Man, the scenario is in the Indian IT industry and I have received an offer letter from company X.