They arranged an installation with me and I requested that they come to my workplace before 3 as I leave the office just 3

They arranged an installation with me and I requested that they come to my workplace before 3 as I leave the office just 3. The guy promised that they will have long arrived. Called their call centre around 2 telling them the same thing cause I saw that time is running late and they promised to deal with the matter. Now I get an sms that their technician is coming after 5:20 when I have long left the agreed place of installation. I am finding this unprofessional they don’t stick to agreed time arrangements