diff --git a/downloadversionIRdata.py b/downloadversionIRdata.py
index 1d6972b2f253510b1707194c221b11db42f16a2e..6861b09314821f25766ef005f1dc6d94a548cbdd 100644
--- a/downloadversionIRdata.py
+++ b/downloadversionIRdata.py
@@ -2643,7 +2643,7 @@ def download_heatflux_by_times(port,tstart,tend,time_window=0,threads=1,testmode
                 if verbose>0:
                     print(now,"download_heatflux_by_times: heat flux data is not available")          
                 if request:
-                    f=open(heatflux_requestlist_path+str(now.year)+str(now.month-1)+"_q_requests.txt",'a')
+                    f=open(heatflux_requestlist_path+str(now.year)+str(now.month)+"_q_requests.txt",'a')
                     try:
                         programid=AKF_2.get_program_id(tstart)
                     except Exception as E: