You can merge your offline wallet with your online wallet by following these steps :
- Open my.electroneum.com and login to your Wallet Manager
- On right you will see "Import from Offline Wallet" , click that
- It will show you STEP 1 :You will see a box where you will need to enter your ETN Wallet Address and hit Next

- In STEP 2 : Enter your Private View Key and press Next
- In STEP 3 : Enter your Private Spend Key and press Next
- Here Electroneum messes up again and shows Step 5 instead of Step 4 , They are habitual of messing up
- In STEP 5 : Review your wallet address is correct and hit Confirm
- Now they show Step 4 : Verify your PIN
- You will be told that the transaction will be verified and information has been sent to the blockchain and just hit Finish
Your Transaction will be added in Recent Transactions and once the amount is retrieved from the blockchain it will reflect in your wallet. They will deduct a little fee
Hope it helps