@Roseline 

I should remind you that the washing machine is not a supported device type by Tapo or Kasa smart plug. Continuously controlling an unsupported load may increase the risk of damage to the plug and could potentially lead to other safety-related issues. You can check this article to learn more about What types of loads can the Tapo/Kasa plug support?

As for the reported issue, it seems like you're using an automation, correct? You may find this article help: What can I do if the Smart Action/Automation doesn’t take effect as expected?

If your goal is simply to turn the device on and off at specific times (e.g. turning it on at 11:30 PM and off two hours later at 1:30 AM), I would recommend using a schedule instead. It's a simpler and more convenient solution for this type of use case. Set Up Schedule, Away Mode, and Timer for TP-Link Tapo Smart Plug/Bulb/Switch in Tapo App