YouTube Premium charged twice

Today I got YouTube Premium Family Plan, sadly, I later found out that my family member can’t join my family because of country difference.

So I decided to get an Individual Plan. Went to “Manage Subscriptions” thing and changed Family to Individual and GOT CHARGED SECOND TIME!

How do I get refund and why the heck did this happen?

A similar situation when I got Individual Plan on Apple Music, then upgraded to Family Plan and I was charged with difference only. Which is fair actually.