点击运算，并没有错误提示，但仍然不显示计算结果。
在view test中的notes for model 显示如下
Computation of degrees of freedom (Default model)
Number of distinct sample moments: 820
Number of distinct parameters to be estimated: 80
Degrees of freedom (820 - 80): 740

Result (Default model)
Minimization was unsuccessful
The results that follow are therefore incorrect
Function of log likelihood = 640299233.957
Number of parameters = 80
请问Minimization was unsuccessful是什么意思？怎么修改好呢？