You could write simple mail as follows :
You are requested to kindly submit your daily reports to _________ by _________ (date).
In future, kindly do send the report on _______(date) each month on regular basis as required by the management.
We look forward to your kind cooperation.
Add anything more that you want to express. The mail should be polite, to-the-point and business-like.
5th August 2007 From India, New Delhi
This is just friendly reminder requesting you to please send your Daily sheet .
Also Going forward , I kindlu request you to please do the needful in sending the report on regular intervals as required by the Management.
Your co-operation to the Management in this regard is highly appreciated .
Your name ..
Hey let me know how did it help you .
5th August 2007 From India, Hyderabad