There HAS to be a simple answer you say? But we live in a very un-simple time.
There are Catholics who cry out: “How come this was a sin when I was a kid but now it’s not!?!”
It depends on what you are talking about.
If you are talking about a sin which the Church has always called a sin, but a particular priest is buying into contemporary secular beliefs that it is not a sin, then you have a rogue priest and you might want to shop for a better confessor.
If it is a sin that requires a more full explanation somehow and the priest is not grasping it in its entirety or you are not explaining it clearly, go again and explain it better.
If you don’t understand whether something is a sin, ask for more counsel on discernment.
My favorite confessors have usually been at more traditional churches, especially the Latin mass churches. I prefer priests who spend time with you and help you figure things out better so you don’t keep falling in that sin or you don’t keep mistaking something for a sin. They don’t seem to be in a hurry (even if they are in a hurry).
Reconciliation is an important Sacrament and many church members have minimized its importance since Vatican 2. It got kind of confusing in there with some strange interpretations, avoidances, and neglect in seminary education. Some children have received First Communion but not their First Confession! Yet, First Confession always comes first.
Truth remains true. That should be simple. But some of our spiritual counsellors have been misled on certain truths. “The greatest sin of our generation is that we have lost our sense of sin”
However ALL priests are ordained to pardon your sins, whether they are good confessors or not.