Loss reason 215: Creative Filtered - App Bundle Exclusions
What it means
The promoted app bundle is excluded.
215 is on the current list and is absent from OpenRTB 2.5. That older list reported a blocked app bundle as 206 and stopped at 213. OpenRTB 2.6 points ${AUCTION_LOSS} at the current list, where 215 is the bundle exclusion and 206 is the store-id exclusion.
The exchange reports this code by expanding the ${AUCTION_LOSS} macro in the bid's loss notice URL (lurl). A bidder that does not set lurl never sees it, and never learns why it lost.
What the exchange checked
The exchange compared the promoted app bundle with the publisher's bundle exclusions.
What to change
Remove the bundle from this inventory. An exchange that still speaks the 2.5 table sends 206 for this condition and does not send 215.