我做面板，现在想消除子相关，但是出现这样的提示，各位大虾怎么办啊？

. xtgls jsr lfdi lwage lroad lconsume li ltax lht ljgmy ler s,panels(he) corr(psar1)
(note: 1 observations dropped because only 1 obs in group)
year is not regularly spaced or does not have intervals of 1 -- use
the force option to treat the intervals as though they were regular