Change MTU on network connection

I recently switch ISP settings and having an MTU of 1500 causes upload issues. I need to change the MTU to 1400 however doing this within HAOS is coming up with a few blockers in that root doesnt seemingly have permissions to execute the command:

ip link set dev eth0@if23 mtu 1400

nets the result that the operation isnt permitted. Trying to sudo states that sudo command not found due to it being a docker image.

Is there any way that I can set this on the device or via config?