just boycott Tesco , let the manager know you won't be shopping with them until they restore the contracts .
if enough people sent twitter , facebook and email messages they would take notice
Tesco Customer Services
Telephone 1850 744 844
https://www.tescohelp.com/tesco/forms/cs_roi_form.html
btw refuse to use the self service counter , you are helping tesco reduce staff hours by using self service tills