error 3200 in stochastic frontier

[Carlos Freitas]

Hi,
I'm trying to estimate a stochastic frontier in a matched sample. The method used was entropy (Entropy reweighting to create balanced samples (Hainmueller, J. 2012)):

ebalance tratamento sexo assist coop sefinanc urbano idade25 idade26a35 idade36a45 idade46a55 idade56a65 sabeler fundinc fundcomp exp1 exp1a5 exp5a10 , tar(1)

However, when I use the weight generated in the pairing (_webal) in the stochastic frontier, the following error appears:
sfcross lnvbp lnareatot lntrab lnins lncap [aweight=_webal] if tratamento==1, nolog

sfcross lnvbp lnareatot lntrab lnins lncap mills mills2 [aweight=_webal] if tratamento==1, nolog

(sum of wgt is 6.0790e+03)

quadcross(): 3200 conformability error
moptimize_util_sum(): - function returned error
mopt__calluser_lf2(): - function returned error
opt__eval_nr_lf2(): - function returned error
opt__eval(): - function returned error
_optimize_evaluate(): - function returned error
_mopt__evaluate(): - function returned error
_moptimize_evaluate(): - function returned error
_moptimize_search(): - function returned error
moptimize_search(): - function returned error
moptimize(): - function returned error
_Get_SoLuTiOn_and_PoSt_ReSuLt_cs(): - function returned error
sf_est_cs(): - function returned error
<istmt>: - function returned error
r(3200);

Do you have any idea how to solve the problem?
Thank you very much!