You can enable a Try Again for Free automation for each subscription plan you have active. This offer can only be claimed once and will not be sent again after a second cancellation.
Navigate to Marketing > Try Again for Free and click New Automation. You'll then choose the plan you want to apply the automation to and set the Amount of Days you want to provide a free trial for.
Of course, have a read over of each email and if you want to add your own personal flair to them, go right ahead.
The first email will go out after 30 days and the second 7 days after that if they haven't claimed the free trial offer.