diff --git a/ports/nordic/common-hal/watchdog/WatchDogTimer.c b/ports/nordic/common-hal/watchdog/WatchDogTimer.c
index b20aa0c0629..48db5014800 100644
--- a/ports/nordic/common-hal/watchdog/WatchDogTimer.c
+++ b/ports/nordic/common-hal/watchdog/WatchDogTimer.c
@@ -75,9 +75,6 @@ void common_hal_watchdog_feed(watchdog_watchdogtimer_obj_t *self) {
 
 void common_hal_watchdog_deinit(watchdog_watchdogtimer_obj_t *self) {
     if (self->mode == WATCHDOGMODE_RESET) {
-        if (gc_alloc_possible()) {
-            mp_raise_RuntimeError(MP_ERROR_TEXT("WatchDogTimer cannot be deinitialized once mode is set to RESET"));
-        }
         // Don't change anything because RESET cannot be undone.
         return;
     }
@@ -164,6 +161,10 @@ void common_hal_watchdog_set_mode(watchdog_watchdogtimer_obj_t *self, watchdog_w
         }
         nrfx_wdt_enable(&wdt);
         nrfx_wdt_feed(&wdt);
+    } else if (current_mode == WATCHDOGMODE_RESET) {
+        // raise exception on attempt to set mode back from RESET to None
+        mp_raise_RuntimeError(MP_ERROR_TEXT("WatchDogTimer cannot be deinitialized once mode is set to RESET"));
+
     }
 
     // If we just switched away from RAISE, disable the timmer.