Does the GFCI test and reset properly when pressing the buttons to do so? Depending on the exact model of the GFCI tester, it may be giving you a false reading, but we would like to look into this. I suggest you submit a claim at www.leviton.com/qualityconcerns so we can evaluate the specific GFCI+tester combination, and send out any necessary replacements. You can also call us up at 800.824.3005. Let me know if there's anything else I can help with.