We checked your domain settings and found you're using third party name servers. In this case, you'll want to contact your web hosting provider to see why your sites go up and down frequently. The domain names themselves are active and we currently don't see any issues with your settings.
Yes, you can do this by setting DNS and creating an A record. Keep in mind setting DNS will override any existing settings you have on the domain (for example, name servers).
How do I create an A record to point my domain to an IP address?
Select "My Domains" from the left-side menu bar and click "Manage Domains" in the drop-down.
Check the box next to your domain name(s) and click on the "Action" button.
Choose "DNS Settings" from the "Action" list.
On the DNS Settings page, select the "Dynadot DNS" setting from the top drop-down menu.
In the "Domain Record (optional)" section, select "A" from the drop-down menu and then enter your IP address in the "IP Address or Target Host" box.
In the "Subdomain Records (optional)" section, enter "www" as the subdomain, select "A" from the drop-down menu and then enter your IP address in the "IP Address or Target Host" box.
Press the "Save Settings" button to save your changes.
Please be aware it might take some time for your settings to propagate.