diff --git a/libraries/utils.robot b/libraries/utils.robot
index ebdeb6e..892d457 100644
--- a/libraries/utils.robot
+++ b/libraries/utils.robot
@@ -569,7 +569,8 @@
     [Arguments]      ${serial_number}
     FOR    ${I}    IN RANGE    0    ${olt_count}
         ${sn}=    Get From Dictionary    ${olt_ids}[${I}]    sn
-        ${of_id}=    Run Keyword IF    "${serial_number}"=="${sn}"    Get From Dictionary    ${olt_ids}[${I}]    of_id
+        ${of_id}=    Run Keyword IF    "${serial_number}"=="${sn}"
+        ...    Get From Dictionary    ${olt_ids}[${I}]    of_id    ELSE    Set Variable    ${of_id}
     END
     [Return]    ${of_id}
 
@@ -578,7 +579,8 @@
     [Arguments]      ${serial_number}
     FOR    ${I}    IN RANGE    0    ${olt_count}
         ${sn}=    Get From Dictionary    ${olt_ids}[${I}]    sn
-        ${olt_device_id}=    Run Keyword IF    "${serial_number}"=="${sn}"    Get From Dictionary    ${olt_ids}[${I}]    device_id
+        ${olt_device_id}=    Run Keyword IF    "${serial_number}"=="${sn}"
+        ...    Get From Dictionary    ${olt_ids}[${I}]    device_id    ELSE    Set Variable    ${olt_device_id}
     END
     [Return]    ${olt_device_id}