diff --git a/main.py b/main.py
index 421447b..fc15a9d 100644
--- a/main.py
+++ b/main.py
@@ -155,13 +155,14 @@ async def fastapi_dump_inp(network: str, inp: str) -> bool:
 async def fastapi_run_project(network: str) -> str:
     global lock_simulation
     
-    if lock_simulation.locked:
+    if lock_simulation.value == 1:
         raise HTTPException(status_code=409, detail="is in simulation")   
     
     with lock_simulation.get_lock():
         print('lock simulation')
         lock_simulation.value = 1
         result = run_project(network)
+        lock_simulation.value = 0
         return result
         
 # put in inp folder, name without extension