Pearson Vue — Flaw of PTE academic registration site

Website:

home.pearsonvue.com

During registration for PTE academic exam, I was asked mandotorily to fill the surname, whereas my passport doesn't have it mentioned there . Though I read all ID policies and knew that I dont want to mention my surname there but without entering anything in surname field it would not move ahead .How do i know that a comma or full stop has to be entered there if no surname is existing . There should have been a text next to the "Name" column on the registration form saying that " PUT comma full stop etc if no surname ", I have seen many such cases here also.then so many people would have not suffered . Not sure why the company is not adding this line there, and not even admitting that its there fault, probably, to harass us and make us pay them again and again . This doesn't seem to be a professional behavior from a company having such a repute in India.