After the last maintenance I’ve had nothing but issues with the POG skills. I can touch the buttons and it shows that the buttons for the skills are being depressed but the skills are not being used even though I have the correct amount of points to use the skills. The only 2 skills on the bar that seem to work with any regularity is the guardian skill and the elephant and I have to press those 10-20 times to get those skills to work.

Try reinstalling the game or resetting the phone (reset phone turns the phone off then boots it back up). That worked for me.