Handy cache flusher command

Here’s a handy cache flusher command. Works fine on Mint 20.3
sync && echo 3 | sudo tee /proc/sys/vm/drop_caches

I could not get this to work… any wise words?
I am continually rebooting some sites… my cache HAS TO BE overloaded!

What distro and version are you running?

Mint Cinnamon Una 20.4

It’s telling me “invalid argument”

Did you copy and paste the command into your terminal from my first post?