Confirmatory factor analysis- negative shared variance

Hiya - I seem to be struggling with my analysis tried several ways to resolve the problem and was unsuccessful. I not sure why my variances comes out negative
This is my code
cfa.mr <- 'A.mr =~ AM.numeric + AR.numeric'

fit.cfa.mr <- cfa(cfa.mr,
se = "robust",
data = dat)

summary(fit.cfa.mr,
standardized = TRUE)

this is the output:

Estimator ML
Optimization method NLMINB
Number of model parameters 4

                                              Used       Total

Number of observations 1766 2232

Model Test User Model:

Test statistic NA
Degrees of freedom -1
P-value (Unknown) NA

Parameter Estimates:

Standard errors Robust.sem
Information Expected
Information saturated (h1) model Structured

Latent Variables:
Estimate Std.Err z-value P(>|z|) Std.lv
Antisocial.mt =~
AM.numeric 1.000 3.207
AT.numeric 3.266 NA 10.475
Std.all

0.366
1.102

Variances:
Estimate Std.Err z-value P(>|z|) Std.lv
.AM.numeric 66.456 NA 66.456
.AT.numeric -19.342 NA -19.342
Antisocial.mt 10.284 NA 1.000
Std.all
0.866
-0.214
1.000