It might be just me misunderstanding the system as I created my first multiclass character - Howler - Mage Slayer/Troubadour. 

As I understand you pick one skill per level, except when you reach new power level, when you choose one skill of each class. However, both times I chose Chanter skills first, after which it took me to Barbarian tree, where I pick second skill but then it takes me back to Chanter skill tree, with my previous choice is still active and makes me pick yet another skill - 3 skills per lvl total. It happened twice, both times I chose chanter skill first, which appears as a second skill tree.

I think it happens when you put one of your point in your "Second Class" first.

This point didn't count, then it takes you to your "First Class", then your "Second Class".

 

To summarize, I think Points have to be spent "In Order", but I don't really know, just assuming.

I think it happens when you put one of your point in your "Second Class" first.

This point didn't count, then it takes you to your "First Class", then your "Second Class".

 

To summarize, I think Points have to be spent "In Order", but I don't really know, just assuming.

That would be my guess.

 

I think it happens when you put one of your point in your "Second Class" first.

This point didn't count, then it takes you to your "First Class", then your "Second Class".

 

To summarize, I think Points have to be spent "In Order", but I don't really know, just assuming.

That would be my guess.

 

 

I also thought this so i tried many ways of levelling up but anything i did let me have 3 points.

 

I got a response from Cdiaz about this and he said that their external team found the bug as well.

 

Here's the thread:

https://forums.obsidian.net/topic/95262-able-to-pick-3-abilities-at-new-power-level-multiclass/

Ah! How it is that I can never find previously reported bugs!

Ah! How it is that I can never find previously reported bugs!

 

Same here! 

New : Could spend two points in the same Class