Legitimate entities typically do not ask for upfront payment to recover funds.
There is no 'legitimate entity' that can help you recover your funds. BTC tx's are irreversible, so if they are lost, you cannot recover it. Except somehow the person who stole from you is arrested and you win a case against them in court, this is very unlikely and you have a higher chance of winning a lottery twice a day, than for this to happen.
Thankyou for your help. I did not send any more money!!
Good! Take the loss as a lesson and move on.