If you played our early version of the game (0.20.1515) and unlocked 'City Marathon' - you may have discovered that the level is locked again - since you updated to the latest version of the game.
This is because the unlock criteria for the level changed between those versions. The downside is that 'City Marathon' is now locked, the upside is that you now have our brand new level 'City Mayhem' unlocked for free!
We had hoped to avoid any quirks like this when moving from the early version to full release but unfortunately this one was unavoidable. We apologise and hope that it won't impact your overall enjoyment of the game.
- The same issue can occur for Desert Marathon, and Snow Marathon - due to a change in unlock condition from version to version.