Hank here from Shopify.
When the SSL is pending and has gone outside of the domain propagation period (up to 72 hours), it is usually an issue with the DNS settings.
Is your domain a Shopify purchased one, or was it purchased from a third-party?
If it is a Shopify domain, within your admin, within (Online Store > Domains > Mange > DNS Settings) and edit the A record if it does not have a value of 188.8.131.52. This should be the only A record value that your domain should have.
Or if your domain is a third-party, you would need to complete these DNS changes on your domain hosting site, but I have the steps located in this guide.
Let me know how you get on, or if you have any additional questions!
All the best,
It very much could be, but somethings the old DNS settings may transfer over.
Can you check the above within your admin and see what A record is showing for you?