I recently traveled to Cabo. I filled out the online forms and brought the printed hardcopies. The Immigration form was accepted but the Customs Declaration form was rejected by the officer who was manning the red and green buttons.
Please refer to the attached pix of the front and back of the back of the form. The front side of the half that you fill out is where you declare whether you are carrying more than $10,000, and the back side of that same half is where you declare whether you are bringing in plants and other prohibited goods. Usually, the officer tears out and takes the filled-out half, and gives you the half that has the instructions and regulations on front and back.
The officer then sent me to the table to fill out the form manually. When I returned to him with the hand-filled form, I asked him what was wrong with my online form.......and here is the key takeway:
When you print this form on both sides of the sheet of paper, make sure that the half that has the "carrying more than $10,000" declaration on the front also has the the "prohibited goods" declaration on the back of it, and not the back side of the instructions and rules.
There may be other reasons for them to be rejected, but that was why mine was rejected.
