Hi. I'm using Stata 15.1/MP and am running into an error that I've not seen before. The model is using 324,000 observations with 35 df and 45 clusters.

Code:
. xtset statefip
       panel variable:  statefip (unbalanced)

. xtlogit y i.year $xvar $zvar if keep, vce(robust)

Fitting comparison model:

Iteration 0:   log pseudolikelihood = -199588.67  
Iteration 1:   log pseudolikelihood = -190549.35  
Iteration 2:   log pseudolikelihood = -190362.87  
Iteration 3:   log pseudolikelihood = -190362.34  
Iteration 4:   log pseudolikelihood = -190362.34  

Fitting full model:

tau =  0.0     log pseudolikelihood = -190362.34
tau =  0.1     log pseudolikelihood = -180501.31
tau =  0.2     log pseudolikelihood = -180570.24

initial values not feasible
r(1400); t=98.77 17:21:29
The r(1400) code is "numerical overflow." Since the model used to run fine, I'm wondering if I screwed up the memory settings somehow.
Code:
. memory

  Memory usage
                                            used                allocated
    ---------------------------------------------------------------------
    data                             770,302,975            4,362,076,160
    strLs                                      0                        0
    ---------------------------------------------------------------------
    data & strLs                     770,302,975            4,362,076,160

    ---------------------------------------------------------------------
    data & strLs                     770,302,975            4,362,076,160
    var. names, %fmts, ...               246,690                  362,858
    overhead                           2,130,424                2,130,712

    Stata matrices                             0                        0
    ado-files                            235,518                  235,518
    stored results                        17,277                   17,277

    Mata matrices                        136,000                  136,000
    Mata functions                       134,368                  134,368

    set maxvar usage                   2,164,426                2,164,426

    other                                255,809                  255,809
    ---------------------------------------------------------------------
    grand total                      775,259,271            4,367,513,128
r; t=0.00 17:31:33

. q memory
-----------------------------------------------------------------------------------------------------------------------
    Memory settings
      set maxvar           2048       2048-120000; max. vars allowed
      set matsize          800        10-11000; max. # vars in models
      set niceness         2          0-10
      set min_memory       4g         0-3200g
      set max_memory       .          4g-3200g or .
      set segmentsize      64m        1m-32g
r; t=0.00 17:31:45
The model fines as -xtreg-. Any thoughts? Thank you!