Terrible service call experience

Your warranty service calls are terrible!!

2 times now for the same computer, your tech didn't have the part on the day of the appointment, and had to schedule. I am now waiting for the 3rd appointment!!

• On 1/7, I used WhatsApp for support on my Dell OptiFlex 7080. Eventually it was decided that a MOBO replacement is needed, and the rep scheduled a service call. 
• On 1/8, I got an email from Dell saying the service call is the next day. Per email, "You can also message us, I asked in WhatsApp to reschedule my appointment, was told to discuss with the tech person when they contact me. 
• On 1/9, Unisys tech Luis emailed, so I asked him to move to Thu or Fri, which he moved to Thu 1/12, 2-4pm.

So far so good...

• On 1/12, at 4:20pm, 20min after the appointment window, I called and texted Luis , he said "The part was shipped back to Dell, I had to relaunch the ticket and overnight the part for tomorrow... I'll have to reschedule for tomorrow as long as the part arrives on time... you will be receiving more detail by Dell. For reference Incident#70961195".

That was pretty disappointing, you didn't have the part, didn't tell me, only informed me when I asked after the appointment time was over. Is that good customer service?

• on 1/13 morning, I got a WhatsApp messages saying my case is closed, I replied to say that's not right, your rep replied "The technician is expected to arrive between Mon, Jan 16, 2023 8:00 AM and Mon, Jan 16, 2023 6:00 PM. You'll be up to date with any scheduling changes related to part availability."
• On 1/13 at 9:21pm, I got a text from Dell, "Dell Msg: Dispatch is scheduled on 2023-01-16T08:00 to 2023-01-16T18:00. Reply STOP to end updates.". 
• On 1/16, apparently, Unisys tech Raymond emailed me at 7:54am, the email said "I can be reached at *INSERTYOURUNISYSIPHONENUMBER*, Best Regards, *INSERTYOURFULLNAME*, Unisys"...

Really?? There is no validation check to see if critical fields are filled in when your company sends emails out?!?

• then I got a text at 9:12am saying "Dell Technologies representative has been scheduled to attend your  between 1/16/2023 1:00:00 PM - 1/16/2023 5:00:00 PM pending parts availability", I confirmed the appointment using the link in the chat, and got another text with Raymond's cell number.
• At 12:48, I texted Raymond to confirm he is coming. After a bunch of back and forth, eventually he said "I'm sorry, I don't have your parts." and we had to reschedule, again.

Dell, really now, 2 times, you didn't have the part ready, and you scheduled and confirmed appointments with me?!?

Don't you think you should confirm the part is available, days before the appointment, or at least the night before the appointment, instead of wasting my time?

Why do you tell me you can't come after the appointment windows expired or just right before, and only when I asked?

Don't you think your customers have lives to live and should not be expected to rearrange our lives around your incompetent service calls? From a scale of 1 to 10, how do you rate your own service?