It sounds like they just don't like their current food
Some owners have to go through all sorts of different brands before they find something they actually like, and many still leave things like alfalfa pellets
I would try and change them over to something different though, any food that is made for more than one animal species is not going to be any good as it will not meet their specific nutritional needs. Also seeds are very fatty so any mix that has these as one of their main ingredients is going to be quite unhealthy.
I believe you live in the US don't you? If so see if you can find Hazel Hamster food, that is the equivalent of our Harry Hamster food and is absolutely fab!
Wean them onto it slowly by mixing the two foods together and slowly increasing the amount of new mix and decreasing the old stuff until they are just eating Hazel Hamster, that should avoid any nasty tummy upsets
You may have to try a few different foods but you are bound to find something they love eventually