Prepositions in professional communication

Our company will remain closed (a)   23.10.2022 to 25.10.2022.

We will complete the work (a)   the 23rd of this month.

1. Attached are the details (a)   your purchase.

According (a)   our records, these invoices have not been paid.

I'm forwarding your request (a)   our sales team.

Please contact me (a)   your earliest convenience.

Thank you (a)   advance for your help with this matter.

I look forward (a)   hearing from you.

I should have an answer for you (a)   the end of the day at the latest.

I need to check (a)   my supervisor first.