Worst Service ever

This company charges a lot for offering a internship in some of cities around the world. They are supposed to investigate the eligibility of the company in order to get a visa. However, they realized the company I was accepted in, was not elegible. They gave the letter for the consulate one week before the program started. I had to pay for a priority visa service for over 300 dollars because of their mistake. I had to arrived to the program 10 days after i was supposed to. They promised me first to change the dates of the internship, however, this was a whole bunch of lies, as the housing dates could not be changed, as London Nest was supposed to leave the facilities the day i was supposed to leave on first place. After about 100 calls, which mainly were all unanswered, they offer me a partial refund, however, they only refund me for 5 days, as they were expecting to buy an airplane ticket on the same day that the visa arrived. Then they did not accept me on the Facebook group, and when i was about to ask the refund, they told me that how can I ask for a refund if i did not go to any of the events, which were announced on the Facebook group. Finally, I got a refund for only 5 days, and they payed via paypal, but they did not cover any of the charges, so I got a refund minus paypal charges.
The staff was so rude and unhelpful.