That’s because you only configured your Google Sites for www.biglotsbulk.com.
Now you need to forward biglotsbulk.com to www.biglotsbulk.com.
One way is to let Cloudflare handle this for you. First, go to your Cloudflare DNS page and create a proxiedA record for biglotsbulk.com with the dummy IP address 192.0.2.1. Then go here to create a Redirect Rule:
Another option is to let Google handle the redirection. But while I’ve not tested this myself, Google support article linked below notes that “Address mapping is supported only by HTTP and not HTTPS.”, so I’d just let Cloudflare handle this.