diff --git a/code/espurna/sensors/BMX280Sensor.h b/code/espurna/sensors/BMX280Sensor.h
index 71d6fbbc..67a1137d 100644
--- a/code/espurna/sensors/BMX280Sensor.h
+++ b/code/espurna/sensors/BMX280Sensor.h
@@ -149,6 +149,7 @@ class BMX280Sensor : public BaseSensor {
             _chip = bme->begin();
             if ((_chip != BMX280_CHIP_BME280) && (_chip != BMX280_CHIP_BMP280)) {
                 _chip = 0;
+                i2cReleaseLock(_address);
                 _error = SENSOR_ERROR_UNKNOWN_ID;
             }
 
diff --git a/code/espurna/sensors/SI7021Sensor.h b/code/espurna/sensors/SI7021Sensor.h
index 3828ee1b..5c59ee1e 100644
--- a/code/espurna/sensors/SI7021Sensor.h
+++ b/code/espurna/sensors/SI7021Sensor.h
@@ -75,6 +75,7 @@ class SI7021Sensor : public BaseSensor {
             #endif
 
             if ((_chip != SI7021_CHIP_SI7021) & (_chip != SI7021_CHIP_HTU21D)) {
+                i2cReleaseLock(_address);
                 _error = SENSOR_ERROR_UNKNOWN_ID;
             } else {
                 _count = 2;