Issue with LockService object

[FRANCOIS RENARD]

Hi,

I have a trigger timebased (every fifteen minutes), and I want to make sure that script triggered is completly done before another trigger starts to run.

So I'm using getDocumentLock - and WaitLock fucntion()

It works most of  the time, but after a while, i don't know why, waitock is ok but a script is  still running !

Thanks for your help !

Here is my code 

// every 15 minutes

function trigger_run()

{

  let b_ok = true;

  let lock = LockService.getDocumentLock();

  try

  {

    lock.waitLock(2000);

    Run_script();

    SpreadsheetApp.flush();      

  }

  catch (e)

  {

    Logger.log(e);

    b_ok=false;

  }

  finally

  {

    if (lock.hasLock()) lock.releaseLock();

    return b_ok;

  }

}