Client complaining nails have faded

I did a clients nails last week as they were going on holiday. They text me today saying could they have them re-painted because theuv faded.
These are gel nails and I refuse to believe the colour could have faded as I locked it in with two topcoats. They told me that they have been in the pool a lot, I think that the shine of the topcoat has faded which has just made them look a bit dull so if I just get her round to pop another top coat on, it will restore the nails shine and lift the...

Client complaining nails have faded