When you place a door (wooden or iron) next to an active redstone power source, the door does not open automatically like it should. See also MCPE-21523.

Steps to reproduce:

1. Place a redstone block.
2. Place a wooden or iron door adjacent to the redstone block.
3. Notice that the trapdoor does not open like it should since it is being powered.

Giving the door a block update will not cause it to open, due to the way redstone works in Bedrock Codebase. Not even powering it with another power source will work, since it is already technically powered. You have to disable/remove the redstone block and then place it again to make the door open. This is especially a problem with iron doors, which can't be opened/closed by hand.