Android Cant mine gem lvl2

Are you sure you researched the lvl 2 gem gathering ?

 

So, you're saying that you did this research


and you fully finished it (it's not still being researched with a timer) and it still won't let you gather from the Level 2 Gem Nodes?

What exactly do you see when you try to gather them?
Are you sure you're not on the wrong location to gather one? E.g. you're not on the Lava and are trying to gather a node that's on the Lava.
Are you sure it's not still Exclusive to another clan for the nodes that spawned as Greed?

Did you try force closing your game and trying again?
or even Clearing your Tech Tree in settings? (You'll want to do this on Wi-fi if you don't have unlimited data)

 

If you tap on the Node level 0, you'll see that it's one of the Shrine realm rewards (like the greedy reward or generous reward)
The Level 1-3 nodes you need to research to gather.