Maybe you have not met the requirements for the hidden route.
For that you must reach at least one end of every character. (There are four characters)
Then you should be able to do it...!
Viewing post in There's no such thing as a harem comments
Maybe weeks 2-4 are the wrong places to go.
As indicated in the description column hint, the location for weeks 2-4 also needs to be correct.
There are strategy answers on my website below, and I have prepared an English version.
If you need them, please use them.
(Go "Game" and click "All route answers" in There's no such thing as a harem)
https://anomalyxxx.wixsite.com/anomaly