I'm guessing you're on top-tier TV (Full-House or XL) and have made a change to your package. Any channel adds/removals often necessitate a re-bundle to a current package.
The legacy (no longer sold) Full-House & XL included the kids pay channels, the current (Maxit) only includes the kids free channels such as CBBC.
The pay kids channels are now part of the "kids personal pick" which is around £6/month IIRC. You could revert your package change to whatever you had before, or you'll need to ask VM to add the personal pick to reinstate these channels.
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