"more than 2 elements are joined at a single intersection" error?

Solid Edge
1

so i want to create a sketch for a revolve detail, but it keeps telling me this after i draw new lines to get rid of some other error which says that something is open somewhere…

so how do i even fix the “open” sketch in the 1st place to not get this “elements” error ?

2

and after all of those it just says “unable to compute topology information” or smth and crashes after some more random edits?

3

An image of the sketch would be helpful.