1.'I kindly inform you..' is unnecessary.
I kindly inform you thatWe are currently updating our data system and we would appreciate it if you could send us your company’s mostupdated list of employees complete dwith their contact details.
Thank you in advance for your attention and
2. For official correspondence, it is better to use 'we' than 'I'.
3. 'Appreciate' is a transitive verb. So, you say 'appreciate it'.
4. We would appreciate it/We would be much obliged/We would be grateful.
not a teacher