diff --git a/app/src/main/java/org/linphone/ui/assistant/fragment/LandingFragment.kt b/app/src/main/java/org/linphone/ui/assistant/fragment/LandingFragment.kt
index 1d44b5e61..43052f0fd 100644
--- a/app/src/main/java/org/linphone/ui/assistant/fragment/LandingFragment.kt
+++ b/app/src/main/java/org/linphone/ui/assistant/fragment/LandingFragment.kt
@@ -19,9 +19,11 @@
  */
 package org.linphone.ui.assistant.fragment
 
+import android.content.Context
 import android.content.Intent
 import android.net.Uri
 import android.os.Bundle
+import android.telephony.TelephonyManager
 import android.view.LayoutInflater
 import android.view.View
 import android.view.ViewGroup
@@ -137,8 +139,10 @@ class LandingFragment : GenericFragment() {
             }
         }
 
+        val telephonyManager = requireContext().getSystemService(Context.TELEPHONY_SERVICE) as TelephonyManager
+        val countryIso = telephonyManager.networkCountryIso
         coreContext.postOnCoreThread {
-            val dialPlan = PhoneNumberUtils.getDeviceDialPlan(requireContext())
+            val dialPlan = PhoneNumberUtils.getDeviceDialPlan(countryIso)
             if (dialPlan != null) {
                 viewModel.internationalPrefix.postValue(dialPlan.countryCallingCode)
                 viewModel.internationalPrefixIsoCountryCode.postValue(dialPlan.isoCountryCode)
diff --git a/app/src/main/java/org/linphone/ui/assistant/fragment/RegisterFragment.kt b/app/src/main/java/org/linphone/ui/assistant/fragment/RegisterFragment.kt
index 6a6fcfb4a..6682821e6 100644
--- a/app/src/main/java/org/linphone/ui/assistant/fragment/RegisterFragment.kt
+++ b/app/src/main/java/org/linphone/ui/assistant/fragment/RegisterFragment.kt
@@ -19,9 +19,11 @@
  */
 package org.linphone.ui.assistant.fragment
 
+import android.content.Context
 import android.content.Intent
 import android.net.Uri
 import android.os.Bundle
+import android.telephony.TelephonyManager
 import android.text.Editable
 import android.text.TextWatcher
 import android.view.LayoutInflater
@@ -168,6 +170,8 @@ class RegisterFragment : GenericFragment() {
             }
         }
 
+        val telephonyManager = requireContext().getSystemService(Context.TELEPHONY_SERVICE) as TelephonyManager
+        val countryIso = telephonyManager.networkCountryIso
         coreContext.postOnCoreThread {
             val adapter = object : ArrayAdapter<String>(
                 requireContext(),
@@ -183,7 +187,7 @@ class RegisterFragment : GenericFragment() {
             }
             adapter.setDropDownViewResource(R.layout.assistant_country_picker_dropdown_cell)
 
-            val dialPlan = PhoneNumberUtils.getDeviceDialPlan(requireContext())
+            val dialPlan = PhoneNumberUtils.getDeviceDialPlan(countryIso)
             var default = 0
             if (dialPlan != null) {
                 viewModel.selectedDialPlan.postValue(dialPlan)
diff --git a/app/src/main/java/org/linphone/ui/assistant/fragment/ThirdPartySipAccountLoginFragment.kt b/app/src/main/java/org/linphone/ui/assistant/fragment/ThirdPartySipAccountLoginFragment.kt
index 99bbf1215..09c90c40d 100644
--- a/app/src/main/java/org/linphone/ui/assistant/fragment/ThirdPartySipAccountLoginFragment.kt
+++ b/app/src/main/java/org/linphone/ui/assistant/fragment/ThirdPartySipAccountLoginFragment.kt
@@ -19,7 +19,9 @@
  */
 package org.linphone.ui.assistant.fragment
 
+import android.content.Context
 import android.os.Bundle
+import android.telephony.TelephonyManager
 import android.view.LayoutInflater
 import android.view.View
 import android.view.ViewGroup
@@ -141,8 +143,10 @@ class ThirdPartySipAccountLoginFragment : GenericFragment() {
             }
         }
 
+        val telephonyManager = requireContext().getSystemService(Context.TELEPHONY_SERVICE) as TelephonyManager
+        val countryIso = telephonyManager.networkCountryIso
         coreContext.postOnCoreThread {
-            val dialPlan = PhoneNumberUtils.getDeviceDialPlan(requireContext())
+            val dialPlan = PhoneNumberUtils.getDeviceDialPlan(countryIso)
             if (dialPlan != null) {
                 viewModel.internationalPrefix.postValue(dialPlan.countryCallingCode)
                 viewModel.internationalPrefixIsoCountryCode.postValue(dialPlan.isoCountryCode)
diff --git a/app/src/main/java/org/linphone/utils/PhoneNumberUtils.kt b/app/src/main/java/org/linphone/utils/PhoneNumberUtils.kt
index a49f97b20..2123b072f 100644
--- a/app/src/main/java/org/linphone/utils/PhoneNumberUtils.kt
+++ b/app/src/main/java/org/linphone/utils/PhoneNumberUtils.kt
@@ -19,10 +19,8 @@
  */
 package org.linphone.utils
 
-import android.content.Context
 import android.content.res.Resources
 import android.provider.ContactsContract
-import android.telephony.TelephonyManager
 import androidx.annotation.AnyThread
 import androidx.annotation.WorkerThread
 import org.linphone.core.DialPlan
@@ -34,9 +32,7 @@ class PhoneNumberUtils {
         private const val TAG = "[Phone Number Utils]"
 
         @WorkerThread
-        fun getDeviceDialPlan(context: Context): DialPlan? {
-            val telephonyManager = context.getSystemService(Context.TELEPHONY_SERVICE) as TelephonyManager
-            val countryIso = telephonyManager.networkCountryIso
+        fun getDeviceDialPlan(countryIso: String): DialPlan? {
             for (dp in Factory.instance().dialPlans) {
                 if (dp.isoCountryCode.equals(countryIso, true)) {
                     val prefix = dp.countryCallingCode