1, collect evidence. Before recovering the principal, the first thing to do is to collect evidence. This evidence includes contracts, bank transfer records and emails. These evidences can prove your investment behavior and the fact that you were cheated, and provide evidence support for the subsequent recovery of the principal.

2. Seek legal help. If the amount is large, seek legal help. Consult a lawyer or legal aid institution to understand the rights and ways to recover the principal. Disputes in the contract should be settled through legal channels.

3. Complain to relevant departments. If the investment behavior involves financial institutions, complain to the relevant regulatory authorities.

4. Recover the principal through legal channels. If the behavior involves a contract dispute, the principal shall be recovered through legal channels. Apply to an arbitration institution to recover the principal through arbitration. In this process, it is necessary to provide sufficient evidence to prove the behavior and the fact of being cheated. If the investment behavior involves a criminal offence, the criminal responsibility of the offender shall be investigated through legal channels, and the defrauded funds shall be recovered.