This phenomenon indicates your campaign has reached its performance limit, not a lack of budget. When you increase your budget and expand your audience but the results remain unchanged, it's usually because the algorithm hasn't had time to adapt and the ad content (creative/offer) no longer generates new demand. Increasing the budget too quickly can also make the distribution system less efficient.
To improve, you should increase your budget gradually (around 20–30% at a time, every 24–48 hours), avoid directly editing a campaign that's already breaking even, and instead duplicate it for testing. Prioritize changing the creative before changing the target, especially the first 3-second hook and the message. If conversion data is low, consider optimizing for higher-level events to help the algorithm learn faster.
To surpass the break-even point, the deciding factor lies in the creative and campaign structure, not in pouring in more budget.