First of all, the fund will not lose all its principal. Theoretically, only when the net value of a fund is zero will it lose everything. In fact, the net value of the fund will not be zero. Even if the fund meets the liquidation conditions, there will be a sum of money after liquidation. Secondly, if the fund purchased by investors has been losing money, the following methods can be adopted:

1. For long-term investors, if the fund continues to fall, it is not recommended to lighten up. On the contrary, if there are idle funds, it is necessary to add positions. The reason is: although the short-term fund decline will affect the fund's income, if you can make up the position at a low level and invest for a long time, you will not only dilute the position cost, but also get more income in the future.

2. For short-term investors, if the fund continues to fall, you can lighten your position appropriately, and then add your position when the fund falls to a low level, which can dilute the cost.

Generally speaking, a fund is valuable if it is held for a long time. Redeem when it falls, and buy when it rises. This will not only make no money, but also make it easier to lose money.