2017 KTM 450sxf starting issues

I have a 2017 KTM 450sx-f that will not start. Towards the end of the season this year it was getting harder to start, but it would still start eventually and would at least fire. I figured I’d change the spark plug and now it won’t start at all. It has spark, it turns over, and it has an occasional backfire, however aside from the occasional backfire the bikes not even trying to start. I’ve tried everything I can think of so I’m open to any suggestions and would greatly appreciate any help.