udacity - Services not delivered and not responding when asking for resolution

I have enrolled in udacity pro (* months) by paying ****** INR which is equal to ***** dollars on February **th. My first nano degree starts from **th March and I have completed my first data analyst nano degree on **st. So after graduating, I have to receive the career services through the career portal which has to be in my dashboard surprisingly which is not. So I have complained udacity that career portal is not showing in my dashboard on April *nd, which they took more than ** days (**th April) to resolve the issue. Normally these interview prep slots are pretty full and we only get the slots after ** to ** days. Because of this technical glitch from there end. I got it too late and I finally booked my first interview prep slot on **th May. So because of there technical glitch I have lost time here.
So finally it was **th March and I am waiting for the call and hoping that this service will help me in my upcoming job interview on June **th. I finally got the call from Anjela the career coach and after speaking with her I am surprised that she doesn't know anything about technical data science stuff. When I asked about technical interview prep she told me that she can help with only behavioural questions and if I want she is suggesting me to send some links. What kind of interview preparation help is this? I am really disappointed after hearing this.
Even after this I thought since I have a gap in my career I thought at least she would help me in my upcoming job interview and asked her the same for which she told that she will open a slot for me on *th June so that she can help me and asked me to book a slot after ending the call. So immediately after ending the call, I logged in to udacity dashboard and I am surprised to find out again the career portal is missing from my dashboard. I am not able to book a slot which she opened for me. I reached to her and she told me to message udacity support.
So again on **th March, I mailed udacity support that again career portal is missing from my dashboard and I told them I have my job interview on **th June. So asked them to resolve the there technical issue at least within * days, so that I can use their services. Today is July *th (more than a month) and they have not resolved the issue. I even contacted the community manager on slack regarding this without much help.
So udacity has failed me in providing the services to me which they have promised. Also, I reached to my mentor for technical interview preparation and he told me that mentor are not supposed to help students anything related to career services and I am left with no help and I failed in my job interview.
Apart from the above problem, one other problem I faced is: When I am enrolled in the udacity pro I was told that for the next * months I will have access to all nano degrees one at a time when the classroom opens. From last month I can see that udacity is providing immediate access to students who are newly enrolling. Since they are opening the classes immediately for new students I asked them to give me the immediate access for me also which they denied. Since they are opening the classes to new students they should open for me also as promised. So again they cheated me here by giving preference to new students who are paying like only ***** per month and leaving me even though I paid more than * lakh upfront.
The third problem I faced was with the mentors, I mainly enrolled in udacity for mentor support and career services. Mentor support is not at all up to the mark. In the first data analyst nano degree, I didn't realize this as I pretty much knew the concepts before but when I am studying the data science nano degree I realized my mentor doesn't have enough mathematical knowledge to teach me. Every time I ask him math related or some algorithmic related questions he says that is not required. I am completely disappointed in udacity with all services.
I thought udacity will help me in starting the new career and paid ****** Rs instead it failed me in every aspect. It failed to provide me with proper career support, proper mentorship, proper customer support. Because of all this, I failed in my job interview.
Since you failed to provide me with the services I want my money back. I want a refund. Even I contacted udacity for providing resolution and they stopped replying me.