Activities disapearing?

Anyone else notice activities disappearing?

Right now jogging and swimming are missing for solo (and yes, swimming is unlocked), and occasionally soccer goes missing for a few days at a time

Not all activities are available on all days of the week, or all months of the year. That is probably what you are seeing.
Also, you can be too tired to do certain things, especially sporty activities, and as I recall, they are not listed in that case.