diff --git a/app/Services/LinkosDeviceLogService.php b/app/Services/LinkosDeviceLogService.php
index 4811b71..f0459b0 100644
--- a/app/Services/LinkosDeviceLogService.php
+++ b/app/Services/LinkosDeviceLogService.php
@@ -176,7 +176,7 @@ class LinkosDeviceLogService
 
         foreach ($logs as $log) {
             foreach (['conductivity', 'humidity', 'temperature', 'n', 'p', 'k'] as $key) {
-                if (! is_null($v = $log->{$key})) {
+                if (is_null($v = $log->{$key})) {
                     continue;
                 }
 
@@ -267,7 +267,7 @@ class LinkosDeviceLogService
                 'pm25',
                 'pm10',
             ] as $key) {
-                if (! is_null($v = $log->{$key})) {
+                if (is_null($v = $log->{$key})) {
                     continue;
                 }
 
@@ -392,7 +392,7 @@ class LinkosDeviceLogService
 
         foreach ($logs as $log) {
             foreach (['chlorine', 'conductivity', 'oxygen', 'ph', 'temperature', 'turbidity'] as $key) {
-                if (! is_null($v = $log->{$key})) {
+                if (is_null($v = $log->{$key})) {
                     continue;
                 }