Western Dental Services

I've been a patient (Chart # 62259) from this office since August 2018. My last visit was October 31st, 2018 & I suppose to get back on November 28th, 2018 to have tooth extraction. But year end, holidays are coming, my schedule was busy with works & the worse part is I am unable to visit my doctor (He is on vacation until beginning of 2019) & get some medication to control my blood pressure level.
I had called to cancel the appointment, finally i've set up my appointment, 1:30 Pm,
Tuesday, January 15th, 2019.
I received a call from Western Dental, around 4:30Pm on Monday January 14th, 2019 from Tammy, she has to cancel my appointment because she somehow found out my insurance membership wasn't activated... I told her i'll call her back after talking to the insurance to reinstate my membership, but please keep my appointment.
My insurance's agent told me that everything should be fine but she 'd like to call me & Western dental office in the morning just to be sure everything is fine before my appointment.
I called W.D. back ask for Tammy but someone else picks up the phone, this person seems to know the situation & she told me she shall let Tammy know that I called., As the arrangement i'll call to confirm about my appointment in the morning... And I did called, a gail did check her computer & said my appointment is good.
I took a day off work, it take me almost half hour to get there. I checked in, Tammy was asked me twice, I told you to call me first why didn't you call? (I never tell her that I should call back and ask to talk to her specifically) I said I did called to confirm my appointment, the receptionist checked & told me my appointment was still good... Then she told me to have a seat while she calls my insurance back because something goes wrong & my appointment was cancelled, that spot was set for someone else.
She was typing something on her computer, don't even want to answer my question (Her mind was working with something else)
I called & talked to an agent, she said somehow I was assigned to Elk grove office instead by mistake, please accept her apology... She read the note & told me that Robin, another agent was talking to W. D about the assignment... then she ask me if I like her to call W.D. ask them to keep my appointment?-I said no because yesterday when I had the conversation with the insurance company's agent, the issue was Reactivation of my membership and that has been solved.
But something came up today on Western Dental office, someone screw up or they were mistaken with client's appointment or something, I don't know yet, that's why they made up stupid story about the assignment to the different location & they can't accept immediate transfer (to keep my appointment spot) in the middle of the month... I got really mad with the way they team up to mistreated me as the patient, disrespectful, under estimate my knowledge & also insulted my intelligence.
The manager Christina was rude, has no knowledge and acting very unprofessional and very poor customer service skill, covered her workers and blame everything to the insurance company, kept telling me there is nothing she can do other than put me in the earliest available appointment will be February, 6th... take it or leave it & the whole time she never accept their mistake, I was really mad and leave the office after saying some bad words to them...
I called the corporate office and talked to the manager to the details, he apologized for those employees who use their ability & power to switch things around, changing clients's appointment time or date or cancel without notice.
He could feel my anger and tried his best to squeeze me in the appointment on the 23rd of January 2019 at 11 am.
Last night I checked my voicemail, there was a message from Western Dental in Stockton office said that my appointment at 11 am today, January 23rd, 2019 was cancelled because I am not assigned to their office.
I called my insurance this afternoon and found out :They, the front office staff don't want me to come to their office, reason, I have no clue.
My only concern is : They aren't the dentists to serve the consumer, they are just the receptionists, clerks & office manager, are they allowed to refuse to give me the services (Absolutely not from either one of them) and are they allowed to cancel my appointment twice?
I'm reaching out for help, I really need the logic answer. Please help.