Hello, 

I'm currently re-running a dataset and syntax that was previously run (and which worked) in SPSS version 28. However, now that I'm re-running this syntax and data in version 29.0.2, one of my models isn't converging. What's a bit more odd is after getting the warning that the iteration was terminated but convergence has not been achieved, I am getting degrees of freedom that are WAY off (i.e., they should be around 256, but are showing as very high numbers [around 1950827]). The syntax is for an MLM model with a daily diary method, informed by Kenny's actor partner interdependence model (APIM). 

It's odd that it's only with one dependent variable (the others work fine) that I'm having this issue, but it's more odd that it was working just fine in SPSS version 28, but now it's not working. Nothing about the data or syntax has changed between when it worked vs. when it didn't. I've pasted example syntax below. The variables that work vs. don't work are very similar (i.e., similar correlations with IVs, same amount of missing data, similar means, SDs), so there's no clear reason I can see for this happening. 

MIXED
DV_actor WITH Actor_variable_1 actor_variable_2 partner_variable_1 partner_variable_2
  /FIXED = Actor_variable_1 actor_variable_2 partner_variable_1 partner_variable_2
  /PRINT = SOLUTION TESTCOV
  /RANDOM INTERCEPT | SUBJECT(coupleid) COVTYPE(UNR) 
  /REPEATED = partnerid_a | SUBJECT(coupleid*Dailynum) COVTYPE(CSR).  

Does anyone have any insight into this one?

Thanks!