Inconsistency with mesh labels being recognized

I’m having an issue with the way a cube’s labels are being recognized in an example piece of code. In one example script, I group together the boundary conditions 1-6 and it works fine (though it doesn’t serve my need to apply a given value to each boundary separately):

+ on(1,2,3,4,5,6, u1=fi1, u2=0, u3=0)

But when I break out the boundary conditions into different lines, one for each face of the cube (this does fit my need), like this:

+ on(1, u1=fi1, u2=0, u3=0)
+ on(2, u1=fi2, u2=0, u3=0)
+ on(3, u1=fi3, u2=0, u3=0)
+ on(4, u1=fi4, u2=0, u3=0)
+ on(5, u1=fi5, u2=0, u3=0)
+ on(6, u1=fi6, u2=0, u3=0)

it complains with this error:

Warning: – Your set of boundary condition is incompatible with the mesh label.
lab 0 nb 400
lab 1 nb 200
lab 2 nb 200
lab 3 nb 200
lab 4 nb 200

Can anyone point me to the correct way to break apart the boundary conditions?

(Note: I have also opened up a parallel github issue here:
It contains the full code samples as this forum will not allow a new user to upload files)

There is not need to post both here and on GitHub, let’s try to solve this on the issue there.