You need to add a TXT record at the apex/root of your domain (@) with the following content. If you already send mail from another service, you may just need to add include:spf.mail.liara.ir to your existing record.
v=spf1 a mx include:spf.mail.liara.ir ~all
You need to add a new TXT record with the name postal-qzIyus._domainkey with the following content.
v=DKIM1; t=s; h=sha256; p=MIGfMA0GCSqGSIb3DQEBAQUAA4GNADCBiQKBgQDduHIKdj8AdtOZ4rcFrt/P/UCqSvpYhkx4dXRUwcOyVqzfUs+E30Xa/MIJ2L3r+kaZrxkzPMay/rHH3W5rQm97zTHIj8vIVU3sL9ywrYvTnYFMXo/B5934gqRoN1UaA52P67yETDuxV+RwR3iH2sKV2Or18UvWql5ybNHa27VgAwIDAQAB;