how to message someone in the Marketplace

I'm new here and am not sure how the messaging works in the selling threads. I would like to contact someone about buying something and I tried sending a message but it was all guesswork and I don't know if it went through.. thank you

if you clicked the "PM" button under their name - that was sending them a mesg

 

If you look in your Control Panel / Private Mesg - seewhere it says Outbox? Until the other user has read their mesg from you it will remain listed in your outbox

Thank you