I cannot Invite anyone to Home. I've tried multiple email addresses and always get the exact same error: "can't send invite right now". This is true from Android and from laptop. Judging by all the posts this is a longstanding issue with no solution because I never see Google address it.
If you're trying to invite a family member who does NOT have a Google (gmail) account, the Google Home app displays the misleading "can't send invite right now" message. You have to have a gmail account to be a household member.
If your prospective household members have regular gmail accounts, then I don't know why you're getting a "can't send invite right now" error message.
Google Nest Support: maybe you could respond as to whether there's a Google Nest server problem right now.
I'm just another Google Nest customer and was trying to point out that Google Nest gives that same message if you try to invite someone who does NOT have a gmail account. Other customers who were trying to invite someone with, say a Yahoo account, reported that it worked when they switched to a gmail account.