Usually this means you need to upload your dar (the compiled output containing Trade) to the ledger. See #2, #3 in this comment for the two main ways to do this, one of which should be the most convenient for you.
If you have uploaded the dar, this error means your package ID doesn’t match what was uploaded. The best way to avoid this (as well as to make your payloads more pleasant) is to use the Java codegen as part of your build process, so that changes to your Daml always yield a Java codegen rerun and a dar upload to dev server, in lockstep.