how to solve nonlinear with BBsolve

I tried to solve a nonlinear system using BBsolve, but it did not work i got this:

Error in optim(par = par, fn = U, method = "Nelder-Mead", control = list(maxit = 100), :
function cannot be evaluated at initial parameters
Error in BBsolve(par = c(0.9, 1.9, 1.4), fn = g) :
object 'ans.best' not found        

Then when I used dfsane and sane I got this :

Iteration:  0  ||F(x0)||:  7531.03 
Error in R > dfsane(par = c(0.9, 1.9, 1.4), fn = g, control = list(trace 
= TRUE)) : 
comparison of these types is not implemented
In addition: Warning messages:
1: In log(q[1]) : NaNs produced
2: In log(Xr/q[1]) : NaNs produced
3: In log(Xr/q[1]) : NaNs produced
4: In dfsane(par = c(0.9, 1.9, 1.4), fn = g, control = list(trace = 
TRUE)) :
Unsuccessful convergence.

Is there no other way to solve the system?