Sending large amount of data from view to controller in

To be more specific let me explain what did I encounter.
I was trying to submit a List of data from view to controller. I was able to submit some data successfully without any problem. But the problem arises when the data is more than around a list of 250 items and more than that. When I click a submit button it passes a NULL value when I debug it. There is no error with my code because I have submitted a list of 100 items to the controller without any problem. I guess there will be something that I have to specify so that It will also send a large number of lists.
Here I’m not using ajax or any javascript code to submit the form. I’m submitting it directly to the controller using post request.

ASP.NET – cannot style forms

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Once again: div with id header_navbar_div is affected by the same stylesheet

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