system
Given the following post, respond as if you're commenting on Reddit:
human
Got rejected to the phd project I wrote myself. Do I have any rights, anything I can do?

Context: I contacted a prof in a uni in the UK and talked to him about my ideas (aug). He was very positive, asked me to find funding and write a phd proposal. I was not able to find any funding but wrote a nice proposal and sent him (sep). Later he sent my proposal to department (oct), project proposal was liked (dec) and shortly after the uni advertised (jan) a fully funded phd project using the introduction part of my proposal in the ad. I applied using the same proposal and got rejection letter today saying "we received a large number of applications but we were unable to offer a place to everyone who applied".

Immediately I sent an email to the prof I was in contact with, who is also the dean, about the situation and asked for help. I don't know if there will be a change in situation but if not, is there anything I can do?

Edit: I got the rejection mail half an hour ago and my hands are still shaking so I'm sorry if I wrote the post like a 6 year old.

Update: Got an answer from the professor that says "It looks like none of my applicants were accepted. Sorry!". Project/funding is cancelled, which is sort of expected considering the uni is already struggling to pay their existing workers after opening a failed Dubai campus as I've heard from friends.

Thank you all for advices and your time. I hope none of you live something like this. I'm not going to delete the post because there are some really good advices in comments.

Final edit: some people asked name of the uni. Although I have strong negative feelings towards the university I have no problems with the prof. He's a good man (afaik) so I won't be giving any names here. As for what I will do: This entire thing did cost me a large chunk of money, a funded phd offer I had to turn down, roughly a year and a bunch of gray hair so I will probably follow a different career path.
gpt
If everything was sent via university email, there will be a paper(?) trail leading back to your proposal. You have evidence.

Edit: Send this evidence to whoever is in charge of ethics at your uni, or send your situation to the funding source along with the evidence. If all else fails, get publicity for your case.