I have installed WHMCS on my website to offer only web hosting (but no domain name registration). All is fine when the TLDs for the domain name specified for hosting are the common ones — .com, .org, .info, and so forth.
It turns out that one client tried to order hosting with a .monster TLD and received the following error message — “The domain you entered is not valid.” Here is an illustrative screenshot: https://prnt.sc/v93g0l
I imagine that WHMCS can be told what TLDs are acceptable for hosting. But, for the life of me, I cannot find that setting. Using Google does not help because it brings up results related to domain name reselling.
I would appreciate any help you can provide.