I've had this before, if you look up ticket number #50835 is the last time it happened. I don't really want to have to go through the dance of reentering my transactions on my Mac and deleting and reinstalling on my iPhone every time it happens.
8 months ago
Sync issues are best investigated via e-mail as each reason could be different.
Can you please tell me if you have a lot of Scheduled transactions? We are currently investigating a possible issue causing sync problems with Scheduled transactions. The case is very rare and it applies only to a very limited number of customers and the fix will be deployed soon but nevertheless it is possible that you got affected. However, in order to confirm we'd need to obtain a copy of your database which is why it's best if we can communicate via e-mail about this.