Two people signing a contract

Good morning,

I am new to Adobe Sign and following training, I have sent a contract to two people to sign. I have set it so that it goes to one person 1st and then the other however the 1st person has got back to me saying he is unable to confirm the signature as it goes straight to the second "sign here" box.

At the bottom of the email he received it says,

“After you sign *************** contract - final, the agreement will be sent to helen.*********@********.**.uk. Then, all parties will receive a final PDF copy by email.”

Is he doing something wrong or have I set it up incorrectly?

Thank you