Cookie reset

my website use cookie for auth, when i open somthing to new tab from website it auto reset the cookie and logged me out from every where, even if i go to home page(site) manually. Without cloudflare site is working fine.
i have pro plan
things tried
I have already disabled CDN.
Disabled security(site.com/)
bypass cache (site.com/
)
manually bypass cookie in waf

Any leads will be thankful

I did further debugging found that there is call coming from browser to server without cookie and website re-reset the session if there is no cookie in request.

without cloudflare there is no extra call to webiste without cookie