You could try switching to “thanks” if that’s easier to get out than “thank you.” Or even a simple smile and a nod can communicate appreciation when you’re feeling stuck. Sometimes giving yourself permission to take your time you need to finish conversation actually reduces the tension that contributes to blocking. You’re doing your best, and you’re still showing up and trying, which says so much about your strength. If you ever want to explore strategies for easing “th” sounds or working through tension on specific words, speech therapy could be helpful.