When the plastic parts of the washing machine are damaged, you can try some methods to repair it:

1. Use glue: If the damaged part is not large, you can use super glue or special glue for plastics Glue to repair. Apply glue along the edges of the damage and glue the pieces tightly together on both sides. Doing this should restore the plastic part to its original strength.

2. Repair by welding plastic: If you have experience repairing plastic parts before, you can consider using plastic welding agent for repair. This method involves using a heat gun or similar tool to heat the plastic, then glue them together, hold them in place, and wait for them to solidify again.

3. Use self-healing plastic: This material is very popular and easy to use. Simply apply the adhesive on the self-healing plastic to the damaged location, allowing it to bond tightly with other plastics. As this self-healing plastic cures, it becomes a rigid structure.

In short, if the damage to the plastic part is not large, you can use the above method to repair it. However, if for some reason the damage is excessive, it is best to replace it with a new plastic part to prevent it from being unsafe or unreliable to use.