I am facing the same problem.
My website is on Japanese language (ja) in the frontend and I get the url of invitations component like that /members/user/招待状/ (with the ja translation).
And I get the same problem on Simplified Chinese (zh_CN : /members/user/邀请/).
I was looking for a solution and found it here.
I don’t have a solution, but I want to let you know that there are languages and users who have the same problem.