Potential field inversion - VisibleDeprecationWarning

Dear SimPEG users,

When running and inversion on potential field data, sometime the log window shows a warning with the “Beta phi_m phi_m …” etc info for every iteration

…Anaconda3\envs\geoapps\lib\site-packages\numpy\core\fromnumeric.py:86: VisibleDeprecationWarning: Creating an ndarray from ragged nested sequences (which is a list-or-tuple of lists-or-tuples-or ndarrays with different lengths or shapes) is deprecated. If you meant to do this, you must specify ‘dtype=object’ when creating the ndarray.
return ufunc.reduce(obj, axis, dtype, out, **passkwargs)

When there is “more than just a few” of these warnings, the inversion output seems to have little to no correlation with the geological info of the AOI.

I have experimented with various input parameter settings but without a useful result.

Does anybody have an explanation /advice how to get rid of this?