Breaking links/page names?

Hi. While experimenting with Logseq (latest release versions) on mac- (12) and iOS (15) I’m basically immediately running into problems. I’m using to organize myself and trying to create a page an according page hierarchy.

Starting with 00–09 Index I’m linking to [[10–19 Some Area]] from there to [[11 Some Category]] and then to [[11.01 Something]] etc.—and I guess after some back and forth between macOS and iOS something like this happens:

Ie. the suddenly are kind of half duplicates, along 12 Something a page 12 with it’s own “sub-pages” creeps up, some pages automatically have a first line like title:: 11.05 Irgendwas, but that does not seem to completely avoid these problems.

Why is this happening? Is that normal? Am I holding it wrong? Something like 11.02 should IMHO not be problematic filename …