Kong plugins enabled but have no effect

Hi ,
I have install kong api gateway (ubuntu version) and KONGA dashboard on my own server , Let us say i define a service S over the route /x which is acutally kong’s mockbin mapped to print the request sent as it is.
I added a plugin on the route /x (request transformer) and configured it to add a simple test header(x-yz:123)
But the problem here is the plugin has no effect (it’s enabled) , cause when i see the raw request ,no such header (x-yz:123) is found.
looking for any heads up

make sure it’s added successfully? type value and press “Enter” in konga

That wasn’t the error, GO version was ; fixed anyway .Had to use same version of go on both control/data planes to build go-pluginserver again and custom plugin