Q: Reminders: won't sync anymore since 9.3.4

hi there!

i'm using a macbook air, ipad air 2 and iphone 5. all was running well until i updated my idevices to the newest ios 9.3.4!

the apple app "reminders" wont sync to my iphone 5 now anymore. syncing between mba and ipad air 2 works still well. i did not change any settings on any device. i'm syncing the reminders over icloud.

any advice? already tried to manually sync over apple's calendars app. turned reminders sync on the iphone off and on again, didnt do anything.

can some1 help me, please! i would greatly appreciate it.