Friends have disappeared

[Kirkwall]

All my contacts have disappeared on both my phone and kindle. I can't start challenges but friends can add me. When I try to refriend I can't as we're already friends. Tried deleting & downloading again but hasn't worked. Anyone else had this problem? Any ideas how to fix it?

[WendyB]

Weird.

Phone shut it down and go back in and see if it helps

Kindle I found this on google to clear your cache

button at the bottom of the screen, then select “Settings“. Scroll down and select “Clear all cookie data“, “Clear cache” or “Clear history” as desired. A dialog should appear where you can confirm your selection.

Let us know

[Kirkwall]

Thanks for advice sadly it didn't work. I contacted fitbit and they say that kindle isn't compatable with app. Strange because I have used it for years without problem. Stranger still my friends reappeared on my phone without me doing anything despite it being a Huawei which is also incompatible.