Why do my dark red cyclamens turn pale pink?

I am not referring to fading blossoms.

I have purchased two beautiful deep red cyclamen plants for indoors. They are prolific bloomers and I am thrilled with them except that within 2 weeks even the new buds and blooms have faded to a pale pink.

Can anyone tell me:

Why is this happening?

Can I prevent it from happening?

Is this a chemical reaction and if so what is it?

Thank you for any input.