I have the same thing, went to a therapist (normal not speech) who also used to stutter and her advice was actually pretty simple. Stop focusing on it. Because eventually you're never it's because of the stutter and that's the problem. She told me to distract myself and focus on my breath to not thing abt any words and never avoid words since you'll start to scare yourself with these words so what I did that helped is focus on my confidence. It's sounds easier said then done I know and it's very hard but if you're okay with stuttering and blocking you will block less since you're already prepared for it and expecting it and are okay with it. This will make anxiety go down.