How can I secure domain redirection from GoDaddy to my ecommerce site?

[route3ralph]

i have a site i built on shopify, https://routethree-4215.myshopify.com/ and my domain is hosted at godaddy www.routethree.com and i have it pointed to my shopify site. When I add masking, it says the shopify site is not secure and it blocks it, and when i do NOT have masking it resolves to the full URL which i do not want. How can i forward it with masking?

[route3ralph]

I have looked everywhere and i can see no way to contact shopify for support, just ask the community unless you fit in exactly to issues which other members have had. I am guessing moving to wordpress is my best option