This means your budget are not proper and somewhat not according to recommended.
- Ads in the campaign can still appear, but might not appear as often as they could.
- A campaign that's limited by budget can still be successful and help you meet business goals. But there might be opportunities to gain more exposure if you're able to increase your budget.
- Click on "Limited by budget" in the campaigns table to see how much your campaign required , you adjust the budgets by increasing the bids or lowering the bids