[General] help me to write letter

[sakiassaf]

the meaning of letter as the following (Subject: Meeting absenteeism
With reference to our invitation to attend the meeting was held in RIC Main office on 26-2-2017 to discuss the remaining time frame of the project and payments ,,,etc, it is regret to inform you that your absence reflect the careless and the lack of seriousness to work .
So we reserve our right to take the proper action without any notification to any careless or delay from your side.
This is for your information and necessary action.)

Please help me to prepare the same letter

 

[teechar]

With reference to our invitation to attend the meeting was held in RIC Main office on 26-2-2017 to discuss the remaining time frame of the project and payments ,,,etc, it is regret to inform you that your absence reflect the careless and the lack of seriousness to work .
So we reserve our right to take the proper action without any notification to any careless or delay from your side.
This is for your information and necessary action.

Hello sakiassaf, and welcome to the forum.
Who are you writing this letter to? Also, can you please clarify the text highlighted in blue? I don't understand it.