Do you provide a warrant? If yes, could you tell me how long and on what terms?

Hello,

I would like to ask you one question. I have written a letter and there is a small extract: ‘’…Do you provide a warrant? If yes, could you tell me how long and on what terms?’’ Can I use a phrase If yes in this sentence? I am asking because my teacher did not like this. Thank you for attention.

Greta, good afternoon.

I would think “if so” would be more fitting.

Kitos.

Oh, I should have thought about it. Thank you very much, Kitos.

Greta

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