Zoho Campaign low open rate

Zoho Campaign low open rate

I have been using Zoho One, Zoho CRM and Zoho Campaign to make my web application, but since I started using zoho  campaign to send emails, it has low open rate (actually zero for the latest campaign for 2 days)

For people who have more experience or know more about it, what could be other factors, zoho campaign system issue, zoho IPs have been rated low?

is the number really accurate and does anyone know whether it can reflect the statistic realtime or there is a big gap like when you open the email but it takes several hours or days to reflect in Zoho Campaign report?

Excuse me for multiple questions, hopefully there is someone who can help me, appreciate it.