Dear ADDRESSEE,
Just want to let you know that I am now back at my position at ACCOUNT_JOB_COMPANY after a leave of absence due to REASON.
Thank you very much for your understanding and patience during my absence. I very much look forward to be working with you again.
Yours Sincerely,
ACCOUNT_FIRST_NAME ACCOUNT_LAST_NAME
ACCOUNT_JOB_TITLE
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