When VM relaunched their TV bundles a while back (forget the exact date), the pay-kids channels were removed from the "standard" packages and put into a separate chargeable add-on.
It's almost guaranteed here, that you've recently made a change to your package that has resulted in you being moved from a legacy TV bundle to a current one, and therefore the kids channels have gone from being inclusive to a chargeable add-on.
Your choices are probably to either pay for them and otherwise remain on your current package, or go down the 14day "changed my mind" route and regrade back onto your previous package, undoing whatever changes it is that you've made.
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