Need Help To Checking The Grammer?

Hello, chungkayng-- and welcome to English Forums.

Hi. May I speak to xx?
This is Fannie from ABC. Is it convenient to talk for a moment?

We received your SMS saying you've made the payment.
Which bank did you transfer it to? Was it ABC Bank to DEF Bank?

What is the amount you transferred?

When did you make the transfer?

Thank you so much for the information.

Thank you so much for the prompt reply. I have a question.

Why should i use "Is it convenient to talk for a moment?"
instead of "Are you convenient to talk for a moment"

Hi, May i know is there any mistake for below sentence?

Thank you so much for the information. I will update our department and verify the payment for you.

'Inconvenient' is not a quality of people; it is a quality of a situation.

Hi, could you tell me if there is any mistake in the sentence below?
Thank you so much for the information. I will advise our department and verify the payment for you.

Hi, could anyone help to correct the grammer mistake in the conversation below?

Hi. May I speak to xxxx?
xxxxxxxxx
This is Fannie from ABC School. Is it convenient to talk for a moment?
XXXXX
Previously, you signed up private drawing lesson with ABC School. The first lesson is on 12Dec, Saturday 9.00am. May I know if you will attend this coming Saturday drawing lessons?
XXXXXXX
May I know have you made the payment to confirm your slot?
XXXXXXX
You may need to make the payment in advance to confirm your slot. May I know when can you make the payment?
XXXXXXX
Sure no problem. Kindly SMS notify us once you make the transferred so that we can update our account department and verify your payment. Thank you so much and have a great day.

I have underlined some problem areas:

Hi. May I speak to xx?
xx
This is Fannie from ABC School. Is it convenient to talk for a moment?
XX
Previously, you signed up private drawing lesson with ABC School. The first lesson is on 12Dec, Saturday 9.00am. May I know if you will attend this coming Saturday drawing lessons?
XXXX
May I know have you made the payment to confirm your slot?
XXXX
You may need to make the payment in advance to confirm your slot. May I know when can you make the payment?
XXXX
Sure no problem. Kindly SMS notify us once you make the transferred so that we can update our account department and verify your payment. Thank you so much and have a great day.

Hi, thank you for indicating the errors to me. How about these?

Previously, you registered private drawing lesson with ABC School. The first lesson is on 12Dececmber, Saturday 9.00am. May I know if you will attend drawing lessons this coming Saturday?

May i know if you have made the payment to confirm your slot?

You may need to make the payment in advance to confirm your slot. May i k now when you can make the payment?

Sure. No problem. Kindly SMS to notify us once you make the transfer so that we can advice our account department and verify your payment. Thank you so much and have a great day.

It is the underlined part that contains a problem:

you signed up private drawing lesson

You have instead changed to another word. Please address my concerns directly.