Borrowing money is not a common problem, but there are some most effective ways to solve it. Here are some of the most effective methods:

Communicate with each other: First, try to communicate with each other and ask them why they don't repay the loan. Sometimes, it may be because the other party has forgotten it or it is difficult to return it on time. Through communication, understand each other's real situation and negotiate solutions.

Send a formal notice: If the communication with the other party fails, you can send a formal notice and explicitly ask the other party to return the loan. The notice may include information such as the date, amount and agreement of both parties, and require the other party to return the loan within the specified time.

Sue the other party: If the other party still fails to repay the loan, you can consider suing the other party. First of all, we need to collect evidence, such as loan agreement, payment records, communication records, etc. Then, bring a lawsuit to the court and ask the other party to return the loan and pay the liquidated damages.

Seek legal aid: If you have no legal knowledge or experience, you can seek legal aid. Lawyers can help formulate legal documents and handle court procedures to ensure the protection of rights and interests.

Find a third party to coordinate: If you don't want to sue the other party, you can also find a third party to coordinate. For example, you can find an arbitration institution or a mediation organization and seek their help to solve disputes.

It should be noted that borrowing money is still a serious problem and should be solved as soon as possible. At the same time, before taking action, we should ensure that our rights and interests are protected and collect enough evidence to support our claims.