As a first step, please verify that you meet all staking conditions. A common reason for staking being inactive is immature coins. Waiting for your coins to mature takes 100 blocks (30 minutes). During this time your GUI wallet may show that part of your balance as immature.

If your wallet meets all of these conditions and staking is not active, try the getstakingstatus command: 
    For a GUI wallet, open Tools > Debug Console.  Then input the command getstakingstatus
    For a CLI wallet, enter instacash-cli getstakingstatus
You should see an output similar to the one below that shows your compliance with several staking conditions.  If any of these are false, it should narrow down the issue.


If the steps above are unsuccessful, try the following:
    Gracefully shutdown your ICH wallet
    Wait 30 seconds and then restart the wallet
    Wait 5 minutes and then unlock your wallet for staking