Dear Ms. Elena,
I regret to inform you that I wish to give 2 weeks notice of my resignation from the Company. My last day of work will be 30 April 2xxx.
I have been very happy working here for the past 2 years and found my work challenging and enjoyable. However I have obtained a post in which I will have more responsibilities and greater career prospects.
Thank you for your help and guidance during my employment.
Yours sincerely,