Link asset to time series

I have asset hierarchy table and time series table imported, but I want to link asset to timeseries or vice-versa. asset hierarchy table looks like:
level 1, level 2.e1, entity 1;
level 1, level 2.e1, entity 2;

level 1, level 2.e2, entity 3;
time series table looks like:
t1, entity 1, x1, y1
t2, entity 1, x2, y2

when I click asset entity 1 in Explore view, it shows time series data count but the name and description of the time series are empty; when click time series, the count of linked Assets is 0. I do not know how to fix the issue.