layer disappears after extending composition

Hello, I'm in the process of creating travel maps using Adobe After Effects. I have now had to extend my composition from one minute to two minutes and have therefore also manually extended the various composition elements. Everything worked fine, only the water layer disappears after one minute, the rest of the map stays the same. Does anyone have any idea how I can make sure that ALL layers get extended? I have no clue why just the one layer disappears...