AT&T won't recognize my address/unit because my neighbor who has the same address but different unit already has wifi

AT&T customer service has been incredibly unhelpful so I'm deciding to come on here.

I have recently moved into a townhome that is split into 5 different units - I have moved into Unit C, where the landlord who previously lived there (they left a month prior to me moving in) informed me that AT&T is the only internet provider on our street. I was initially very excited to have AT&T Fiber and be an AT&T customer and so I scheduled an appointment to be scheduled on Sunday, 11/20/22 between 10-12pm.

11/20/22:

• Technician doesn't show up - no calls, no text messages, nothing.
• I called AT&T and was told that there is a conflicting name under my account and thus I needed to submit either a utility bill or my lease agreement to the AT&T address validation email. I assumed  the conflicting name was the landlord, who had informed me they they contacted AT&T that they were moving away.

11/21/22:

• Called customer service for a total of 2 straight hours.
• Per the customer service rep, they informed me that the service address on my account did not specify the specifc unit, but rather just had the entire townhome address as the listed service address. My neighbor, who lives in Unit B, has already had AT&T wifi and thus AT&T believed that because I already had wifi, they didn't send the technician on 11/20/22.
• The customer  service rep submitted an address  validation for me, CONFIRMED with me that the validation was completed and approved, and set an installation appointment with me for Wednesday, 11/16/22 between 8-10am. I am working out of the home, and thus  chose a pocket of time where I could be present and had my partner, who took work off for this in the morning, could stay behind as well.

11/16/22:

• 8am: I received a call from an AT&T technician informing me they were on their way to my home. 
• 8:30 am: technician arrived - they called and asked which unit I was in (this should have been my first warning sign) and I told them Unit C. They walked on over and began the installation.
• 12pm: They finally finished the installation and set up the wifi gateway HOWEVER - they informed me that because my service address still did NOT have Unit C specified, something was wrong with my  account and it was merging with my neighbors in Unit B. Although  they had installed the wifi gateway, the technician informed me that if they turned on the new router, it would shut off my neighbors wifi.
• The technician informed me that I needed to call AT&T customer service and ask them to add "Unit C" to my service address. Upon completing that, I would give them the serial number on the AT&T gateway device and have them activate it. At this point, I'm confused as I thought I had completed the address validation and SPECIFIED Unit C. 
• I called AT&T customer service, who then transferred me over to the loyalty department.
• The loyalty department rep said that the technician should not have installed the equipment in the first place, as my address was not validated. I explained that I had already completed the process, but was told by this rep that I needed to do it again. The rep submitted the validation again through the phone, provided me a ticket number, and informed me that I would have to call 2 days later to see if the validation went through - AT&T apparently does not provide confirmation on their end and has the customer do this process on their end. 
• This whole time, I have downloaded the Smart home app manager, which says that my wifi/account is online, however it shows my Unit B neighbor's wifi. I see the service address on there and it was the whole townhome.
• I go to the general AT&T service map to see if unit C is eligible for AT&T internet - when I submit the address, it informs me that I am not, even though the previous tenant who lived here A MONTH BEFORE ME, had AT&T.

11/17/22:

• I am desperate at this point and call customer service again. Customer service said that AT&T is not available at my Unit C address and that I cannot sign up for AT&T. I am confused and then call the loyalty department again.
• The loyalty department submits ANOTHER address validation  for me, and says that they should have fixed the service address to include Unit C and they scheduled me for another installation date on 11/20/22. 
• I am checking my updated appointment on my AT&T account, which confirms my 11/20/22 appointment, however it still does not  have Unit C listed, rather it has a longer zip code. My Smart Home app still says I am connected to my Unit B neighbor's wifi.

Exhausted and frustrated do not even come close to how I am feeling. I am hoping to put this in writing on the forum to alert AT&T of this issue. What's  funny is that at the end of the 11/17 loyalty rep call, the rep is trying to get me to switch my phone service to AT&T to get a deal. This is no shade to the rep themselves as I know that is part of their job, however AT&T, are you kidding me? Why would I want to set up my phone service with you after all of this?

I would  appreciate any sort of guidance and direction as this has been eating up at my brain space. I am a mental health professional that has telehealth appointments and internet IS CRUCIAL for me, and yet here I am without it. AT&T, please do better.