There are two possible reasons for this:
- For a private user account, you may have reached your quota for free paid ads.
- You tried to insert categories such services, business for sale categories & etc...
The error will look like this:
As a private user, there are limitation on number of paid categories for you to insert. For more information, you can view here.
In order for you to continue, you will need to delete the current ad and post a new one or sign up for a Pro Niaga account.