Charge 3 sync and display issues

[StanehiveQuine]

Have a 3 year old Charge 3. 

1) My Charge 3 now struggles to remain sync'd with my iPhone during the day - especially at work if my phone is not with me/in my handbag (as it has to be fwhile teaching in class);

2) Both the school where I work and my home both have an unreliable/weak 3G/ 4G phone signal (have to stand in specific area of school to get any signal; ditto in my home neighbourhood I have to be at specific spots);
Both locations are rural coastal NE Scotland...so cliffs, granite, martiime radio traffic= sometimes there is not even GPRS);

3) Even when the Charge 3 does sync in the morning, before leaving for school it takes 15 mins to do so, then by 10.30 , I have lost 30 mins in keeping  time  (crucial as teacher to have correct time for morning playtime, lunchtime, getting ready for hometime);

4) Lastly I struggle to read the screen outside at all, and even indoors even with it set at its brightlest.

Moderator edit: added label

Moderator edit: updated subject for clarity

[EdsonFitbit]

Welcome to the Fitbit Community, @StanehiveQuine.

I’m sorry to hear about the difficulties you experienced with your Fitbit Charge 3. Thank you for the information provided.

I noticed that you've been in touch with Customer Support. I'm pretty sure they will do their best to provide a high level of support. Thank you for your patience while dealing with this situation.

Have a nice day.