Can someone review the grammar of this sentence for me please, and the use of "Where" here?
Thank you.

Hi aaa,

I am responsible for generating the Customer extract file. I have a question on this instance, 071889-0001, where the string before the hyphen(-) contains an extra zero in the front. Do I need to care that there should be only 5 chars max before the hyphen and 4 chars max after the hyphen, or just remove the one (1) at the end and to make sure that the string should only contain up to 10 chars?

Thank you,
Thi.