Dear {{$employee_name}},
After reviewing your leave request from {{$start_date}} to {{$end_date}}, I regret to inform you that we are unable to approve it at this time due to {{$reason}}.
Please feel free to discuss alternative dates for your leave, and we will do our best to accommodate them in the future.
Thank you for your understanding.
Best regards,
{{$sender_name}}
{{$designation}}