Product: Vehicle loan or lease

In XX/XX/XXXX, I traded in a XXXX XXXX XXXX with only XXXX miles on it and excellent condition due to monthly payments were too high. i needed lower payments. So i found online XXXX XXXX XXXX XXXX with XXXX miles for $ XXXX hoping my payments would go down. XXXX XXXX paid off my car i traded in which was $ XXXX, they literally handed the check to XXXX in XXXX with paid in full receipt. But they added {$4000.00} into my new loan stating that XXXX would give me $ XXXX for the trade of my XXXX. ( During COVID ) I didnt understand how that would be legal. Also due to my credit score, year of the XXXX and miles most banks want down payments to lower monthly payments but I didnt have that so he was working really hard to get me in this vehicle. He said term of loan is 5 years, not what i expected but I said ok. 
So XXXX XXXX XXXX for $ XXXX and rolling in $ XXXX that I owe XXXX so it goes into my new loan which isnt even with XXXX, its with another bank. My payment went from XXXX ( XXXX XXXX ) to XXXX ( XXXX XXXX ) for 7 years and I was told in order to get the loan, i had to get their extended warranty which I later found out they lied and i canceled it a year later but I started getting letters in the mail after i got the loan and my vehicle- banks including their own bank and my current bank which I have the loan through currently stating that i am denied for the loan. These were loan applications processed by the company to banks after i had signed documents and had the vehicle registered and made first payments on it - I was confused so i asked and they said that the rep was no longer working there. Also on my loan i currently have now, i had noticed that it stated it was a lease and a loan ( which how can i be leasing the vehicle if I got a loan for purchasing ) and I was told it was a easy fix by dealership. I am not only upside down by $ XXXX but my payments are insane plus how is any of this legal? I also was in the middle of XXXX when I was trying to do the application online at the time he was trying to get me financed but I wasnt coherent enough so the sales rep offered to fill it out for me and have everything processed for me when I was done my treatment which is another problem because I told him that i have XXXX XXXX XXXX XXXX XXXX so I am often overwhelmed and confused but he assured me that he would never take advantage of anyone especially someone who is XXXX. I trusted him and the company and after my boyfriend looked at my paperwork and the letters I was getting weeks to few months later he said that I needed to find out what is going on. I was told simple errors that wont effect my loan or credit score and I just noticed that my loan is for 7 years which is insane because between principal and interest rate i will be paying almost XXXX for this vehicle with no warranty coverage because i cancelled the one they forced me to buy and paid another company for coverage which i could use but I cant afford to get another warranty due to income as i am permently XXXX and i have bought vehicles in the past. All i wanted was something used to bring down payments, but I know everything about XXXX vehicles since I have owned them since XXXX XXXX XXXX. But I am declining in my health and my sister told me that I needed to report this today because she knows that once i send this, I will not remember as I have early XXXX XXXXXXXX. Please if you can help me and others by looking into this. Thank you. I can send you letters and copies of everything if you need them of the denying loans after purchase agreement was made and sold to me by representative.