Community Moderator Alumni are previous members of the Moderation Team, which ensures conversations are friendly, factual, and on-topic. Moderators are here to answer questions, escalate bugs, and make sure your voice is heard by the larger Fitbit team. Learn more
Hello @Joshua762, thanks for joining the Fitbit Community, it's great to have you on board! 
This seems like a very odd situation, when did you start experiencing it? Have you restarted your Charge HR and your Flex 2 lately? If so, when you finish using one tracker do you sync it before taking the other one? It's possible that if the first tracker didn't sync the information before using the second one, the information of the second one will rewrite the information of the first one.
If you use your Flex 2 for normal use, please sync it before switching to your Charge HR when working out and when you finish sync your Charge HR before switching back to your Flex 2. Additionally, please remember to keep the tracker you're not syncing apart (another room) when syncing, that way it won't interfere with the one you're syncing and that one will have priority when syncing.
I hope this can be helpful, give it a try and keep me posted in case you need anything else! 
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Community Moderator Alumni are previous members of the Moderation Team, which ensures conversations are friendly, factual, and on-topic. Moderators are here to answer questions, escalate bugs, and make sure your voice is heard by the larger Fitbit team. Learn more
Hello @Joshua762, I hope you're having a great day, thanks for taking the time to reply!
I'm very glad your issue has now been resolved. In case you have some spare time, I would like to invite you to visit our Discussions board where you will find great tips and encouragement from other members and if there's anything else I can do for you, please keep me posted!
Happy stepping!
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