A question about vodafone freedom pack?

[Jake]

Yeah, you should probably get some normal calling credit.. I use the freedom packs too but im not sure about being abroad. If you get normal credit, your freedom pack will be used first, meaning if you don't need the normal credit it will only use the freedom pack anyway.

[Lola]

I'm going to France in 2 weeks and got a 600 text and 300 minute freedom pack to use from now to then and then in France. I tried to text my dad who has bought a new phone in a America as his UK bought phone doesn't work there. When I tried it said I didn't have enough calling credit. I'm wondering if I need to get a normal top-up to call home to the UK or will my freedom pack work when calling UK phones.
Thanks for answers!