after finding the global mode with the mode_compute = 7 (many number of interation and number of fuction evaluation as well) then the likelihood of -2197.2944 can not be improved anymore, Dynare also report that the Hessian matrix is negative. So that MH algorithm can not be computed.
I try with another mode_compute, for example, 4 and 9, but the Hessian is still negative in Dynare and the likelihood of -2197.2944 can not be improved anymore either
Anyone has a good suggestion for me?
Thank a lot

What happens if you try mode_compute = 6? This one is Monte-Carlo based. Another option would be that you load your last mode file and keep searching for the posterior mode. Use the mode_file = yourfile option in the estimation command.

Thank you for your suggestion
But I did it already before asking for help (mode_file=ALEstim_phuong_mode) and try to use another method_mode, for example 9 which seem to be the best mode finder. But the hessian matrix is still negative

I recommend to begin with mode_compute=6 (it always results in positive definite Hessian) and then try another mode-finder e.g. 9 providing result file from 6 as mode_file.

You can clearly see that your “mode” is not at the maximum for b and rdeltay (which are also far away from the prior mode). Try to understand why the model/data push the estimates to that region.