Brink's Global Services review: New door lock and door bell

I recently purchased a new doorbell and smart door lock from Brink's. After the technician installed the new door lock, it would not lock properly. Before leaving, the technician made numerous calls to his department and then informed me that a replacement lock would be sent because the one installed was defective.
After several days, no one contacted me. When I called Brink's, I was told that a new lock should arrive within two days and that someone would call to schedule an appointment to replace it.
Today, the lock stopped making any sound at all. I was instructed to remove the batteries, but I was unable to do so. Before I spoke with Andrew, another representative assisted me. Andrew then told me there was nothing in the system indicating that my lock was scheduled to be replaced. Instead, he said he would arrange for someone to look at the lock.
This was extremely upsetting. I have been living with a door that does not lock properly, and I constantly must remember to check whether it is secured. This has caused me unnecessary stress and concern for my safety.
When I asked to speak with a supervisor, Andrew initially refused. After several requests, he finally transferred me to Shawn. Unfortunately, Shawn did not conduct himself in a manner I would expect from a supervisor. He sounded uninterested and seemed annoyed that he had to take the call. After a lengthy discussion, he stated that someone would bring a new lock on the 17th. However, he said this with no enthusiasm or reassurance that Brink's was committed to resolving the problem. Instead of making me feel like a valued customer, he made me feel as though my call was an inconvenience.
This has been the worst customer service experience I have ever had. At this point, I do not know whom to believe. Either the technician was incorrect when he assured me that a replacement lock had been ordered, or Shawn is now providing conflicting information. Neither situation inspires confidence.
Andrew also mentioned that the service appointment might involve replacing the control panel, but Shawn did not mention the panel at all. I am now confused about what is scheduled. Andrew mentioned that the notes included something about a panel, and Shawn could not answer this question.
Please tell me exactly what I should expect on the 17th.
• Will the technician bring a new door lock?
• Will the control panel also be replaced?
• Will the technician have everything necessary to complete the repair during that visit?
I purchased this security system for peace of mind, yet I have been left with a lock that does not function properly and inconsistent information from your representatives. I expect Brink's to resolve this matter promptly and to provide customer service that reflects the quality of your company.