本人小白,在尝试mplus多层次线性分析检验调节效应时遇到了以下的问题:本身主效应是显著的,但是加入了交互项以后,主效应就变的不显著了

我把代码附在下面求助大神帮忙 十分感谢(AIGCXLSQ是自变量AIGC与调节变量XLSQ的交互项)
DATA:
FILE IS C:\Users\邓又赫\Desktop\无标题20.dat;
VARIABLE:
MISSING ARE ALL (-99);
NAMES ARE id AIGC XLSQ time ZDFW ZWSH AIGCXLSQ;
USEVARIABLES ARE id AIGC XLSQ time ZDFW ZWSH AIGCXLSQ;
WITHIN = AIGC time ZDFW ZWSH AIGCXLSQ;
BETWEEN = XLSQ;
CLUSTER = id;
define:
center AIGC time ZDFW ZWSH(groupmean);
center XLSQ(grandmean);
ANALYSIS: TYPE = TWOLEVEL RANDOM;
ESTIMATOR = ML;
MODEL:
%WITHIN%
ZWSH ON AIGC (b1)
AIGCXLSQ (b_interaction)
time (b_time);
ZWSH ON AIGC (b2);
ZDFW ON ZWSH (a1);
OUTPUT: SAMPSTAT STANDARDIZED TECH11;