Rank up gems not working

Can someone explain to me y my rank up gems don't work on any of my champion I have some 3-4 generic gems 5 star rank up gems but they don't work

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Perhaps they are 2015/2016/2017 gems ?? I’m not having any issues with rank up gems

Thanks you for ur are your advice I look at it they are 2017 gems but generic gems so I don't really understand

Those gems can only be used on champions that were released 2015-2017 depending on the gem.

Who are you trying to use the gem on?

Would you happen to have a screenshot of the screen where the error is occurring?