Questions & Answers about Akwai iyaka.
That is the normal Hausa pattern for existence. Hausa typically says:
akwai + noun
So Akwai iyaka is structured like there is a limit. Starting with iyaka would not be the neutral, standard way to say this.
It can be both. Akwai does not change for singular vs. plural the way English changes there is / there are. The noun and the context tell you whether the meaning is singular, plural, or general.
So depending on context, Akwai iyaka could be understood as There is a limit or more generally There are limits.