How to enter a value in webdatagrid (Infragistics) using Selenium?

Question

I have a Infragistics webdatagrid on one of the web pages I am working. It shows like a table and when we click on any of the cell, it will become like an input box.

I am trying to enter a value into one of the cells using selenium.

The cell initially shows as td element and once we click on it, it will be edited and once we inspect it shows an input element.

So I am first clicking on td xpath and then trying to enter a value like 50, into the input box.

Click is ok as it is showing the input box after clicking but once the selenium script tries to enter a value into the input element, it is becoming immediately uneditable and throwing an error like "Sorry! element is uneditable".

Any one know how to enter a value into the webdatagrid cells?

Thank you.