Hello,
I am completely new here. I hope I posted the question correctly. 
I have a Synology DSM connected to the Home Assistant to monitor the NAS temperature. Today my Synology disconnected from HA and I had to re-enter my login information. Since then, all of my historical data from the entity has been deleted.
The entity has the same ID, but the history still starts from today.
However, after a long time of clicking, I found that if I add the “Statistics Chart” tab to the main panel so the historical data of the entity displays. But there are no dates on the history tab from the same period.
Maybe I didn’t explain it well with my English. Please look at the images below which will show the problem.
I want to ask how I can display/restore this historical data again for the entity? Obviously, HA has this data available.
Thank you very much for the advice. I am a complete newbie to HA.
I wish everybody a nice day.