Hi,
What do you mean by slow down work ? Is it performance related issue or intentionally employee is delaying the work ? Whether this has been discussed with that employee ?
When you need help to draft such advisory notes better provide detailed information because what ever response you may get will be limited to the information you had provided.
One thing vivid from your post is that being key employee you doesn't want to go for warning letter option and want to issue advisory note. There is no standard template for these letter and you need to develop one based on the background of the case. Based on the information provided by you just drafted a letter as below. You may edit as per your requirement.
Dear
As you must be aware, all our efforts and intentions as a Team on the work front aims at 100% Client satisfaction vis-a-viz growth of the Organisation as a whole. To arrive at this we should never relegate the three key components discipline, conduct and punctuality to the back seat, because all Organisations dwell on these basic principles and keep moving on.
Being a senior associate of this Organisation your behavioural and performance pattern on work front should match with your seniority in terms of age, experience and commitment to the Company. However in contrary we observed that of late you are not focused towards your work and your efforts and intentions towards your job have not been manifested rightly to bring about the desired result (i.e.) quality work output. This is not expected from you. We assume this is due to your recent frequent late reporting to office and unplanned leaves. We just want to caution you that you need to consciously manage your time and energy to meet both professional and personal commitments while prioritizing self-care and well-being. Feel free to contact the undersigned for any support you require in this connection.
We hope you will take this advisory note in the right spirit.
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