diff --git a/rdagent/scenarios/data_science/proposal/exp_gen/parallel.py b/rdagent/scenarios/data_science/proposal/exp_gen/parallel.py
index 73a1b0f3..4361a8d3 100644
--- a/rdagent/scenarios/data_science/proposal/exp_gen/parallel.py
+++ b/rdagent/scenarios/data_science/proposal/exp_gen/parallel.py
@@ -83,7 +83,7 @@ class ParallelMultiTraceExpGen(ExpGen):
             else:
                 # enter the merging stage
                 # make sure the all loops are finished
-                if loop.get_unfinished_loop_cnt(loop.loop_idx) < 1:
+                if loop.get_unfinished_loop_cnt(loop.loop_idx) < RD_AGENT_SETTINGS.get_max_parallel():
                     # disable reset in merging stage
                     DS_RD_SETTING.coding_fail_reanalyze_threshold = 100000
                     DS_RD_SETTING.consecutive_errors = 100000
@@ -93,13 +93,15 @@ class ParallelMultiTraceExpGen(ExpGen):
                         trace.set_current_selection(selection=(-1,))
                         return self.exp_gen.gen(trace)
                     else:
-                        selection = (leaves[0],)
+                        local_selection = (leaves[0],)
                         if trace.sota_exp_to_submit is not None:
                             for i in range(1, len(leaves)):
                                 if trace.is_parent(trace.exp2idx(trace.sota_exp_to_submit), leaves[i]):
-                                    selection = (leaves[i],)
+                                    local_selection = (leaves[i],)
                                     break
-                        trace.set_current_selection(selection)
-                        return self.merge_exp_gen.gen(trace)
+                        trace.set_current_selection(local_selection)
+                        exp = self.merge_exp_gen.gen(trace)
+                        exp.set_local_selection(local_selection)
+                        return exp
 
             await asyncio.sleep(1)