Wow, how to downvote answers?
It seems like I have run into a similar issue, and will be contacting support, but came across your post here and just felt that the answer given was really horrible, to be honest
As a note to this, there is no quota counter in quota-limits that shows any information about Function App SKUs, so there is nothing that gives an explanation or more information, or give you any warnings about it, which is quite lame.
And the answer to "just contact support".... without any attempt at what you can even do to find out where this quota limit is located, or any Azure API that you can query to find out what the limit is for this or anything, is basically like showing you a finger. What is the purpose of this forum then if I may ask?