Can you be more specific - with what post type you have issue with or what post type I should check and what steps I should follow to see the issue. Maybe the problem URL will help.
Please check the field "Ensi-ilta" - the date field is empty:
=> hidden link
Now, I see you added the filter to your view:
=> hidden link
Select items with field:
Vuosi is a string equal to URL_PARAM(wpv-wpcf-vuosi)
AND
Ensi-ilta is a number lower than TODAY()
Where - you set - Ensi-ilta is a number lower than TODAY()
so, it seems as the field is empty, it removes the entry, you should try to set the date of tomorrow to the field Ensi-ilta and save it and then check on front-end.
Ah ok... This is a bit complicated setup for me to get working. The Ensi-ilta is a date field that is used sometimes, but not always, so it can be also empty. Is it possible to have it like
Vuosi is a string equal to URL_PARAM(wpv-wpcf-vuosi)
AND
Ensi-ilta is a number lower than TODAY() OR empty