gfit error message in generalized Pareto (GP) distribution

Hello,

I compute return period using gpfit (Generalized Pareto parameter estimates) to calculate the return period, while I calculate the maximum likehood, I got an error message below.

Warning: Maximum likelihood has converged to an estimate of K < -1/2.

Confidence intervals and standard errors can not be computed reliably.> In gpfit (line 124)

I guess this happens with small values in the inputs, but I have no idea how to sort it out. Could you please help????

Thanks