Switched 4 lines to Visible and didn't see spot to enter SWITCH25 Promo - How do I fix that?

[LNR23]

I just switched 4 lines to visible and I didn't see a spot to enter the SWITCH25 promo code at checkout.  Can I apply that promo to the lines still?  Moved one line a few days ago and 3 lines yesterday.

[LNR23]

I chatted with support on Facebook Messenger and they helped apply the discount code to all lines. Great customer support experience!