My King Charles loves, but my Pug not so keen (he's a fussy eater)

Shall I stick to the same food or would it be worth me alternating between this Arden Grange and another food such as Royal Canin Mini or Applaws to try and keep him enjoying his food?

I thought perhaps he is bored of the flavour, they do say variety is the spice of life

Or is he playing me and shall I stick to Arden Grange?