a local hello world flask app behind a reverse ssh tunnel isn't reachable through internet

Question

the hello world example of the flask is run on my laptop on port 5000 and host 0.0.0.0. I create a reverse ssh tunnel with : ssh -R 5000:localhost:5000 usr@my-vps-ip the curl localhost:5000 on my VPS will return the expected result. I expect that curl my-vps-ip:5000 must also return the expected result too, but I get Failed to connect to my-vps-ip 5000: Connection refused. stoping the firewall isn't solved the problem. I tested this with ngrok, and that is working. I'm doing something wrong?