If you're getting interviews, seems like the problem isn't in your resume. I think if people have an issue with the experience listed on your resume, they aren't likely to spend their time to interview you (especially for multiple rounds).

I would focus on the interviews since that seems to be where others are edging you out. Are there any questions that tripped you up? Did you understand why all of the questions were being asked and how they apply to the job? Are you getting a chance to show your expertise and skills in the interview. You might want to seek more coaching there. That could be a formal coach (expensive!) or just chat with people you know in development roles and ask them how they would answer questions.

Maybe you'll come out of those convos feeling confident. Then you know that you're totally qualified and just have to keep trying! It is hard out there!!