Everything trying on local machine: Windows 10, Vercel CLI 35.2.2, node v21.7.1 Using Visual Studio Code

On the http://localhost:5001/ i have sveltkit application fetching my server

Server is running http://localhost:3000/
Code with honojs looks like this:

If from client side headers and body are present, when I get the error on the client side:

and on the server:

and log to console on server side: POST: api/pricing---> never hit

If I comment out headers and body:

when no errors on both sides.

Package json looks like this:

Found similar topics with CORS problems: #10927

but downgrade to vercel cli to version 32.0.1 didn't help:
still get: TypeError: Response body object should not be disturbed or locked

Thank you for your help

P.S. Created the cloudflare worker with the exact honojs code - and everything works fine. So it means, that the problem is not in Hono.js