Errors:  

- recently made

- in your hotel

- office meeting

Corrected version:

I have recently made a reservation at your hotel for an office meeting on the 25th of August.

Improved version:

I have recently made a reservation at your esteemed hotel for an office meeting scheduled on the 25th of August.

Errors:  

- booked 

- for 25th to 28th of August 

Corrected version:

I reserved two single bedrooms from the 25th to the 28th of August, along with a meeting hall.

Improved version:

I secured reservations for two single bedrooms from the 25th to the 28th of August, in addition to booking a meeting hall.

Errors:  

- Missing article ("a") before "change."

Corrected version:

However, there is a change in the schedule.

Improved version:

However, there has been a modification in the schedule.

Errors:  

- Incorrect article ("room" should be plural: "rooms").

Corrected version:

Firstly, single rooms should be upgraded to luxury rooms.

Improved version:

Firstly, I kindly request that the single rooms be upgraded to luxurious accommodations.

Errors:  

- we are planning to serve

- after meeting

Corrected version:

Moreover, we plan to be served snacks and lunch after the meeting.

Improved version:

Furthermore, we intend to provide refreshments and lunch following the meeting.

Errors:  

- are planning

- 26th August to 30 August 

- incorrect plural form ("equipments" should be "equipment")

- office meeting

- missing articles ("a" before "microphone" and "a" before "screen")

Corrected version:

Furthermore, we have planned to shift the dates from the 26th of August to the 30th of August, and we need equipment for the office meeting, such as a microphone, projector, and screen.

Improved version:

Additionally, we propose rescheduling the dates from the 26th of August to the 30th of August. Furthermore, we require essential equipment for the office meeting, including a microphone, projector, and screen.

Errors:  

- As the dates are changed

- Incorrect word order ("so might be we require" should be "we might require").

- more guests can arrive

Corrected version:

Since the dates have changed, we might require one more luxury room, as additional guests could arrive.

Improved version:

Given the altered dates, it is possible that we will need an additional luxury room to accommodate potential extra guests.

Errors:  

- Kindly help us 

- arrangements 

- any query, 

- please do 

Corrected version:

Please assist us with the arrangements, and if you have any queries, feel free to write back.

Improved version:

Kindly facilitate the necessary arrangements, and should you have any inquiries, do not hesitate to reach out.