Fidelity ADT poor service

We have had shocking service from Fidelity ADT. It took them weeks to get back to out premises to complete the installation. Also, they never rep**** to my e-mail complaint sent more than a week ago. Their technicians are hours later than arranged and are double booked at times, as confirmed by Joanne, the technical services manager. She confirmed she is bypassed on occasion with technicians being booked. Wee