What causes ads not filling?

Ad requests return no fill because mediation is misconfigured, the network has no inventory for the region or format, or test and consent settings block real ads.

How do I catch this when it only happens for some players?

Capture it automatically from the player's device with the full stack trace, the device and OS, the build, and a breadcrumb trail of what they did. That turns a vague complaint into a specific, reproducible issue you can fix without owning the hardware it happens on.

How to Fix Ads Not Filling in a Mobile Game

Quick answer: Set up mediation with multiple networks, request the right formats for each placement, handle no-fill with a waterfall, and verify consent and region settings.

Ads not filling is a mediation and configuration problem. Here is how to improve fill.

How to fix it

1. Use mediation with multiple networks

Relying on one ad network leaves gaps where it has no inventory. Mediation across several networks fills more requests, since when one has no ad, another may. Configure a mediation waterfall or bidding.

2. Handle no-fill gracefully

When no ad fills, do not block the player — skip to the reward or content with a fallback. Treat no-fill as expected and design the flow so it does not soft-lock waiting for an ad.

3. Check region, format, and consent

Fill varies by region and format, and missing consent (GDPR, ATT) can block personalized ads or all ads. Verify the placement format, the regions you target, and that consent is handled so real ads are eligible.

Catching the ones you can't reproduce

The hardest version of this to fix is the one you can't reproduce — it only happens on a player's hardware, OS, driver, or save state, under conditions that simply aren't present on your machine. A report that says “it crashed” or “it froze” gives you nothing to act on, so the bug survives release after release while quietly costing you players.

Automatic error capture closes that gap. Each failure arrives with its full stack trace, the device and OS, the build number, and a breadcrumb trail of what the player did right before it broke, so even a failure you have never seen becomes a specific, reproducible issue. Fold identical failures into one signature ranked by how many players each hits, and your worklist sorts itself worst-first instead of arriving as a stream of vague complaints.

This is where a tool like Bugnet earns its place. Its SDK captures every mobile error automatically with the full stack trace plus device, OS, memory, build, and game-state context, folds duplicates into one grouped issue with an occurrence count, and ties each to the build it first appeared on — so you fix the problem that hurts the most players first and confirm it is gone when its signature disappears from the next release.

A crash you can name from its stack trace is a crash you can usually fix in minutes.