Let it be their idea

One thing that has helped me the most, is a little phrase someone taught me over 30 years ago.

Let it be their idea.

The long and short of that was,  I wanted to tell my bosses,  their sales strategy was not working and, hu-hum, my idea was the best.

(Like, I knew anything about sales other than what they taught me.)

Thankfully an intermediary, stepped in to say, do the thing that you want them to change. If it is beneficial as you suggest,  then they will end up telling you to do it that way, letting it be their idea.

If you can detach from ego, that they are taking credit for your idea, it is a win win.