Weeknum function error - can't get ISO week

[MAG_PRG]

From all the documentation I have seen, this DAX code should give me the ISO week number for today:

Week = WEEKNUM(Today(), 21)

But this is giving me an error, saying 21 is not the correct parameter type. When it gives me the available options, only 1 and 2 appear:

The documentation here seems to clearly state that 21 is a valid option for return_type:
https://learn.microsoft.com/en-us/dax/weeknum-function-dax

Does anyone know why it will not accept 21 as the parameter?

[v-yangliu-msft · Accepted solution]

Hi  @MAG_PRG ,

According to research, a similar issue has been reported internally.

I will update here once I get any information.

Best Regards,

Liu Yang

If this post helps, then please consider Accept it as the solution to help the other members find it more quickly.

[jk13]

I have the same issue with my existing WEEKNUM function!

WEEKNUM(TODAY(),2) is giving me since yesterday also the "Parameter is not the correct type" error breaking many reports..