10-25-2016 07:47
10-25-2016 07:47
10-26-2016 00:22
10-26-2016 00:22
I think you may be right about the two problems being linked. It can only alert you about a low battery when it sees a low battery when you sync. So, if you are having problems syncing then it won't know about it.
In the hope that the problems may be software related you might want to try restarting your fitbit using this procedure:
https://help.fitbit.com/articles/en_US/Help_article/1186/
If that doesn't work then it may be defective. Are you still within warranty? If so, it might be worth contacting customer support: