Count Unique values between two dates - if the value has not appeared at all

[Cambo99]

Hello,

I need to count the unique values of a list between two dates - but only if that particular value has not already appeared. Some context might help.
I have a list of all customer receipts with the data as follows;

Column A: Receipt date
Column B: Customer name
Column C: Receipt amount

I need to know the number of new customer receipts that have been receipted in a particular date range (from cell G7 to cell H7). I can count how many receipts have been made by using the COUNTIFS function, but I have not been able to limit this to new customers only.

My current formula is =COUNTIFS(A:A,">="&G7,A:A,"<="&H7)

I am now stuck with how to add the criteria for unique names / values.

Can someone please help?
Many thanks in anticipation

 

[Cambo99]

Awesome - this formula works EXACTLY as I need it to. Thank you so much for your input - really appreciate it

 

[Aladin Akyurek]

Awesome - this formula works EXACTLY as I need it to. Thank you so much for your input - really appreciate it

You are welcome.