Are you using that only for a USB charger? Or for other appliances? If your charger is the only thing you are using it for, if that charger is an Apple, it might be designed for their own Apple Euro plug.
https://www.apple.com/shop/product/M...el-adapter-kit
Or, something like this:
https://www.amazon.com/Europe-Conver.../dp/B0777R8H1K
Several years ago I bought a USB charger with a Euro plug with the intent to only use that when I travel. Then Covid happened and have not used it for years now.