Hey Mike,
This is a validation bug that crept into the last update. The good news is the team is working on actively squashing it at the moment.
It's being caused by the Minimum Time Between Each Occurrence setting cannot exceed the value in Recurs Every minus 1 day. That is to say if you are recurring every 1 Days you need the value in Minimum Time Between Each Occurrence to be set to 0. The bug is preventing the UI from telling you about this.
I appreciate this is frustrating. On the bright side there is a way to workaround this in the meantime:

To work around this for now you will need to set the Minimum Time field first as it becomes disabled when the Recurs Every field is lowered to a single day. Doing so should allow you to create the configuration shown above. From there your Activity Plans should create sessions as expected.
I'm grateful for your patience while the team gets this sorted.
Cheers,
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Paul Turner
Senior Product Manager
Genesys - Employees
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