panel matrices issue

[tahokovi]

Hi, I was running the panel matrices code and it keeps telling me:

Error in panel.matrices(county.data, unit = 4, time = 3, outcome = 6, : Input panel must be a balanced panel: it must have an observation for every unit at every time.

My panel is balanced which is the weird thing. Anyone has having similar issues? Any remedies?

Thanks in advance!

[changshengspecial]

To fill in the missing values in your data, and it is preferable to ensure consistency in the years of the groups being processed.