Having received no reaction to my first letter, I wrote again on 30/06/2021:
Dear Ladies and Gentlemen,
A month has passed since I reached out to you for help via below message.
Unfortunately I haven't had a single response so far. In good faith I am left to assume that the message did not get delivered at the time.
Could I therefore kindly ask you to
Thank you very much for your time and effort.
Sincerely,