Changes to polls don’t save

I have the paid version of the plugin.
My WP software is current. My plugins are current.
I have two polls every month of the year.
I created the polls for every month in advance. They are all the same template.
Each month I add the options and post the poll This worked fine until April. I thought it was a fluke but once again it’s happening this month. I opened the May Calendar Crab poll, added the options and hit save. Nothing saved and now instead of 0 Answers Count it says NaN in the poll manager view.
In April I had to recreate the poll. Needless to say I’m going to be upset if all the work I put into making these polls in advance to save time is now in vain. 🙁