map connection inconsistency

some maps aren't unlocked when adjacent map is completed despite a connection being shown between them.

just cleared a map near the first pic and it got even weirder:


i labeled them to make it easier to explain (first pic shows maps 1 and 4). i did maps 1 and 2 before starting this thread and map 4 was clearly connected to map 1, but wasn't available to enter. now i cleared map 3 and the layout of the paths changed and somehow map 4 became available despite not having any connections to cleared maps...

update:

map 4 works fine even though it's not connected to other completed maps.

Had the same issue today. Connections changed from 1->2 to 4->2.
And map 3, somehow, got activated without any direct path.