Dimension time bad format

Good afternoon community!!!

I have a topic to correct:

In the company we use that DAX formula to give fomato to the column.

"Num Year Week", YEAR([Date]) &"-"& IF(WEEKNUM([Date],2)<10, "0" & WEEKNUM([Date],21), WEEKNUM([Date],21))

But for certain cases he does not respect it:

For orthos it goes well:

What can I do to fix that BUG?

Thank you!!

Best regards

Ana