[Your Name, & Address here]
[Recipient Name & address here]
Sub – [write Case name]
Case No. [Case no.]
You were served [title of discovery documents] on [date].
The due date for your reaction to this discovery was [due date]. You did not request for any extension for responding to the discovery before this period.
Now, as the due date has gone, and I have not received a confirmed written response from you, I request you to please send me your response within [no. of days] days from the receipt of this letter in order avoid complications in this case.
Thank you for your attention, and cooperation regarding this matter.
Encl: [Enclosures List here]