It seems a strange question: was the universe created? It's generally assumed that the universe was created, whether it's believed that God created the universe or the universe exploded from a Big Bang. How could it not be created? Here we have a universe with stars and planets, and planet Earth with humans, animals, plants, and so on. Something must have made this happen...
The problem with creation is that it implies there is a cause. It implies cause and effect. But cause and effect are only conceptual terms for what seems to happen in the world. It's a useful model, but not wholly accurate. It would be more accurate to say that there is continual consequential change. It's not that one 'thing' causes something to happen, then that other 'thing' causes another 'thing', and on and on. There are not really any discrete or separate 'things'. So the terms 'cause' and 'effect' have an assumption of defined, limited, separate 'things'. The real experience is that there is not one then another then another. It's more that the universe unravels or unfolds continually.
There may appear to be lulls in the flow of change, but these are temporary and ultimately also part of the change. Any appearance of no change is illusory. There is only ever a pretence of stillness in the universe. Just as we may assume that cars parked out in the street are still, whilst really they are spinning through space on a planet that never stops spinning and moving.
We can assume that this appearance of the universe as change and movement came from a point of no change or movement. We can assume that the apparent universe did appear from nothing, yes. But it would be a full, complete Nothing - an unmanifest Singularity, from which everything appeared and in which it appears. An unmanifest Singularity has no time or space. It has no limits. So the creation of the universe is the appearance from this complete unmanifest Nothingness. What caused the appearance of the universe? That's the question.
Cause and effect are already questionable, so can we consider that nothing caused the appearance of the universe? Well, possibly, as what appears appears out of Nothing and in Nothing. Also, there is no appearance without the witnessing of it. Effectively, no seen without the seer. The seen and the seer arise simultaneously - what appears and the witness of this appear simultaneously. The universe and I appear simultaneously. The Singularity seems to divide into the knower knowing the known. It doesn't really divide, because the Singularity is always maintained.
It's difficult to accept that the universe only appears once there is one to witness it. It's generally accepted that the universe appeared long before it created beings that could perceive it. But all we can reasonably say is that the universe that I perceive seems to have existed before I perceived it. But by 'I' we mean the human being. The human being is part of the universe. Is there a possibility that the universe was perceived by that which created it or in which it was created?
So we come full circle to the question of whether the universe was created? Well, what exists is here timelessly, uncreated. Existence itself, or Being, is permanently timeless and formless. This is the universe. The visible or perceivable universe of forms that seems to appear in time and space is like an expression or reflection of Timeless Dimensionless Being. The universe isn't created or destroyed, it only appears to be created and destroyed within the permanence of Being.
That sounds like a complicated answer. The simple answer is that Being is the nature of the universe. It just is.