Sorry for the long post. I thought it would helpful to give some background before asking about my issue. If you can make it through my rambling, I’d really, really appreciate any advice anyone might have. History I’m a bit of a comeback player. I was fairly serious about trumpet when I was younger (I’m 33 now)---got a music major in college and all that jazz. But I ended up pursuing a different career path and I set the trumpet aside for the bulk of my 20’s. I started playing again casually a couple years ago. Then, I’m not sure what happened, but about 10 months ago a real fire started in me and I’m hitting it hard again. Range Improvement Earlier this year I finally admitted to myself that my range needed work. For basically my entire life, my playable range topped out at a high C (two ledger lines above the staff) or D. So, I took a couple lessons early this year with one of the top guys in town to work on it. He showed me some techniques and, to my surprise, my range exploded! I’d always thought I wasn’t trying hard enough or that my body wasn’t built for high notes. Turns out, there’s a technique to playing high and I’d just never learned how to do it. I started gaining serious ground every few weeks. As of about two or three weeks ago, I was consistently playing double C’s and higher as part of my daily warm-up, and my playable range was flirting with double G’s (two G’s above the staff). I even hit a triple Bb once (three Bb’s above the staff). It wasn’t loud, but it was there. Recent Range Deterioration But about two weeks ago, I started going backwards. It’s to the point now where I can hardly play a Bb above the staff. My range has deteriorated past where it was when I started working on it earlier this year. In fact, it’s worse than it’s ever been since I was a kid. I’m absolutely flabbergasted. I can’t figure out what’s going on. I haven’t changed anything in particular in my practice routine. Everything has just stopped. Description of Problem Part of the technique I was learning involved achieving a feeling of resistance while simultaneously puckering and pushing more of my lips into the mouthpiece. It felt almost effortless compared to what I’d been doing my whole life. But now when I pucker and try to find that feeling of resistance, nothing works. Sometimes I can’t get my lips to vibrate, or when I do, there is a sort of double buzz. My chops feel tighter than they should be, but when I relax them, I can’t play above the staff. Sometimes my bottom lip starts curling in in a weird way, but when I correct my embouchure and pucker my lips like I was doing before, the double buzz starts up. FWIW, I’m not using excessive pressure and I don't think I'm practicing too much. I booked an “emergency” lesson this past Friday with the guy who originally helped me earlier this year. He thinks I’ve subconsciously picked up a bad habit, and that I need to get back to the basics. He’s got me doing long-tone exercises and slurs in the medium and low registers. Has anyone ever come across something like this? It’s really disheartening.