If you already see a Minecraft Portal look-a-like in front of you, click that portal to enter the Shrine itself ( Sometimes it's silent, sometimes it's wavy and lastly it's glowing red ).
Don't click what's below your screen ( Even though it said Enter ) or you'll be sent back to the Temple.
If the Portal is silent or wavy, don't bother going. Just go inside when it's glowing red and that way will actually progressing Master Zhen Questline and increasing your chances to meet Nyxara.