My Versa watch and my Aria 2 scale could not connect to my home Unifi (Ubiquity) wifi. I found that Fitbit (unlike Nest, Ecobee, and many others) requires broadcast/multicast to be turned on within the SSID. If you turn this off (which it should be off to clean up/speed up your wifi), you will see a connection with one-way traffic (TX/up with no RX/down). Once I turned on the feature to allow broadcasts/multicasts for the SSID, both devices work fine.
It is unfortunate that Fitbit continues to use features in their devices that cripple our wifi connections. READ HERE if you want to know how Fitbit is slowing down your wifi: https://help.ubnt.com/hc/en-us/articles/115001529267
The Aria 2 image below shows 0 down traffic when broadcast/multicast traffic is turned off. It shows two-way traffic when it is turned on. It was the same for the Versa watch.
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It is great to see you around @S1930.
I really appreciate this information, I know many users that are experiencing this issue will find your post really helpful. If there is something we can help you with, do not hesitate to post it.
Keep the stepping up! 
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