diff --git a/src/math/lp/dioph_eq.cpp b/src/math/lp/dioph_eq.cpp
index d2f69926a9..d0dd0a9e22 100644
--- a/src/math/lp/dioph_eq.cpp
+++ b/src/math/lp/dioph_eq.cpp
@@ -671,6 +671,7 @@ namespace lp {
                 return;
             }
             m_added_terms.push_back(t);
+            m_changed_terms.insert(t->j());
             auto undo = undo_add_term(*this, t);
             lra.trail().push(undo);
         }