I ran through the tutorial and didn't get the same issue that you are having when I ran myContract.increment()
Suggest you check the address that you specified in truffle console:
https://docs.zeppelinos.org/docs/upgrading.html Make sure you replace with the address of the upgradeable instance your created of MyContract . This address was returned by the create command we ran in the previous section, which is the same as the one returned by the update command we ran above.
Thanks @abcoathup - I was using the Ganache first account. Switching to the second one fixed the issue. Can I suggest you add a note to the tutorial documentation as I am sure this would catch a few people out