If your domain is registered with One.com, you can access your DNS Zone from your One.com control panel, under the DNS tab.
You can find detailed tutorials on creating, editing, and deleting DNS records at One.com here:
Hostinger default DNS records:
If you face any difficulties while managing DNS Zone at your domain provider, it’s best to contact One.com directly. Alternatively, you can transfer your domain to Hostinger so your hosting and domain will be managed from one place 😊