Thank you guys for your comments. I think I have identified my root problem/ inefficiency. I believe I have been overblowing since the day I started playing. I think I have always put too much air through the trumpet which has always caused my tone quality to dampen. I have been working way too hard and not having enough fun. I just realised this yesterday. Now that am trying to not overblow, and let my lips respond to less air, my range has decreased dramatically. I actually feel like Im starting from zero since I’ve never played like this before. But I hope that I have identified my root problem/ inefficiency so that I can finally improve my playing.