I can see that the nameservers in the whois have changed, but not in the parent zone:
** Domain Servers:
henrik.ns.cloudflare.com
olivia.ns.cloudflare.com
didemkara.com.tr. 43200 IN NS ara.ns.cloudflare.com.
didemkara.com.tr. 43200 IN NS karl.ns.cloudflare.com.
;; Received 99 bytes from 31.145.253.159#53(ns73.nic.tr) in 76 ms
As it’s been half an hour already, I doubt this will change with more waiting, but it is possible.
But the nameservers in the parent zone need to be updated to add the domain to your Cloudflare account.
didemkara.com.tr. 43200 IN NS henrik.ns.cloudflare.com.
didemkara.com.tr. 43200 IN NS olivia.ns.cloudflare.com.
;; Received 104 bytes from 185.7.0.3#53(ns42.nic.tr) in 72 ms
The site should now become active in your Cloudflare account within minutes.