correct verb form [you are going to pick up] [you are picking up][you pick up]

[ansonman]

I have made up the sentences below.

(1) Thank you for your online order. I will email you when it is ready. If this is the first time you are going to pick up an order from our store, please bring a piece of ID.

(2) Thank you for your online order. I will email you when it is ready. If this is the first time you are picking up an order from our store, please bring a piece of ID.

(3) Thank you for your online order. I will email you when it is ready. If this is the first time you pick up an order from our store, please bring a piece of ID.

I am not sure which verb form of "pick up" is correct. Thank you for your help.

[Alan]

(2) is more idiomatic than (1).

(3) is incorrect.