If the green Call button doesn't appear on a listing, it simply means the seller chose not to show their number.
- That's a normal and common choice: many members prefer to exchange only in writing.
- In that case, use the Message button to reach them: they receive your messages exactly the same way.
Chat lets you arrange everything (questions, photos, meetings) without needing the phone. It's also safer, since you don't have to reveal your contact details.
If you are a seller and want to show your number, republish or edit your listing and turn off the “Hide number” option.