Hi, @natarsha91 !
It may be a a case of having exceeded the URL redirect limit - the Shopify limit for URL redirects is 100k. Or the more likely culprit here, is your domain set up. From the sounds of the error(ERR_TOO_MANY_REDIRECTS), it seems like it may be that you have more than one A Record in your DNS settings. Shopify requires only one A Record which points to our IP address: 184.108.40.206.
I have run a DIG on that domain, and your subdomain and root domain do appear to be set up okay. Had you made any changes to your DNS settings recently? It could be a propagation delay. If the domain was purchased and hosted on Shopify, it might be worth trying to reset the DNS settings. Before trying this, just make sure you make note of the DNS settings that are currently set up there in case you're using anything custom from a third party.