I'm trying to insert Speed Module 3 into Assembling Machine 3 and for some reason it's inserting Speed Module 2 instead. It doesn't do this with any other machine as far as I've noticed. In the Module Inserter itself, it shows Speed 3s, but it actually orders Speed 2s and I don't see why it would suddenly start doing that after years of working just fine.

Edit: Seems every single module I try to insert into the Assembly Machine 3 becomes Speed 2...

Well, never mind, it was user error - I didn't see that I'd already chosen Assembly Machine 3 earlier in the GUI. Why can I select the same machine more than once??

Holy hell bro, I wasnt being able to insert modules, and couldnt figure out. Turns out I was having the same problem you mentioned here!! Thanks for writing the solution.
And yes, I agree that its kinda absurd to be able to select same machine >1

Glad I could help lol, hope this gets fixed at some point

Should be fixed in the next version. The fix will only prevent you from doubling configurations, it won't fix presets with duplicates.