In article ,
Jose wrote:

went back to NorCal and cancelled IFR, [...]
When I reported back on the [practice] missed at Tracy
and requested flight following back to Hayward (KHWD)
I was asked to cancel IFR.

Maybe they didn't receive your original cancellation. Either NorCal
didn't really cancel, or they didn't transmit the cancellation properly
(would Tracy have advance strips on you?)

"Tracy", being an uncontrolled airport in NorCal's area, wouldn't have
any strips at all :-). I was on the same NorCal approach frequency the
entire time from before I cancelled IFR to when I got the instructions
to report cancelling IFR some 40 or more minutes later....

Hamish