This is the option I am adding to the ivprobit that I am using.

difficult first tolerance(10) ltolerance(10) nrtolerance(10) qtolerance(10)

How can I get "backed up" error when I loosen all tolerances to this extent? Why is this happening?

And I found that which control is causing the problem. But simply dropping this control might look too non-rigorous for a scientific standard. What would you recommend doing?