When a $$k subfield is present, the call number formating is lost

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Whenever we have a $$k subfield in the 852 field, the call number formatting specified in "Tweak and Test" is not used. If the $$k subfield is not present, the spine label prints correctly. However, having the $$k print at the head of the spine label is important for the organization of our collection.

We get
youth
QL737.C22
I83
2020
education

instead of
youth
QL
737
C22
I83
2020
education