I don't know. I don't remember the last time I tried renko charts. But how I would check what is working and what is not - I would place some blocks here and there to print information for me and if certain information stops printing, then the problem can be located more easily.
Try this to see if the EA stops reacting at some point: 0_1525550973799_f869e2b7-1394-48ae-b606-84d068c886dd-image.png