student finance struggle

Once again - student finance have left me in a horrible state. I re-applied for my 3rd year the moment applications opened but instead of actually doing their job, they did not connect my application to my dad's account (he's the only parent that supports my application) despite having done so for my previous applications and for my sister's first application this year. I have uploaded the pff2 form to my acocunt as it did not give me the option to do so through my dad's and other documents they asked for regarding my parents divorce, depsite the fact I had this down in my previous applicaitons but I have checked my application online and it has not registed any attempts of my uploading this and is giving me the minimum maintanace loan despite the fact I am entitled to the maximum loan (It is what i recieved in 1st and 2nd year) - as my sister, who I will re-itterate has the the same parent supporting as I do, has been offered the maximum. I do not understand what student finance have done, why they make communicating with them so difficult (I have called on several occasions, but it is very difficult to get through and the chat function does not work properly) and why they could not have simply connected my account to my dad's again like it has done for the last 2 years. I am incredibly stressed, and worried as that will not even cover my rent next year, depsite renting one of the cheapest properties available, nevermind supporting me living.