Regularization and nonlinear greybox model parameters identification

I need to identify 10 parameters of a nonlinear grey-box model. When I use the regularization (by adding this line of code: opt.Regularization.Lambda = 1e-4; ) approach to reduce uncertainties related to parameters estimation the following error appears: 'Dimensions of matrices being concatenated are not consistent' Also when I try to define the matrix R ( opt.Regularization.R = 0.5*eye(10,1);) this error appears : 'The "R" regularization vector must contain 12 positive entries.' I do not understand why the length should be 12 knowing that the number of parameters is 10. If anyone knows what's going on please let me know