. estat abond

Arellano-Bond test for zero autocorrelation in first-differenced errors
  +-----------------------+
  |Order |  z     Prob > z|
  |------+----------------|
  |   1  |-3.1827  0.0015 |
  |   2  | -2.424  0.0153 |
  +-----------------------+
   H0: no autocorrelation


请问这种情况该如何处理？