If you downgrade to the Free plan, any channels above the limits of the Free plan will become locked. We would recommend removing any channels that you no longer need, which will then unlock the channels you're looking to keep.
If you'd rather not delete any channels (for example, if you would like to keep them connected in case you upgrade again in the future), you can choose which channels to unlock using the steps below.
Click on your profile avatar at the top right of your dashboard and then click Account from the drop down menu.
Click the Channels option from the menu on the left hand side of your screen.
Click the three-dot menu next to the channel you wish to unlock and then click Unlock Channel.
You will now see a window showing all of your channels. Tick the checkboxes to the left of the channels you’d like to keep active. Channels not ticked will remain (or become) locked. If you attempt to keep more channels active than your plan limits allow, you’ll see an error message.
If a channel is locked with posts still scheduled in its queue, the posts will remain in the queue, but won't publish until the channel is unlocked. Once unlocked, you might need to reschedule some of your posts if the posting time has passed.