diff --git a/pleskdistup/common/src/leapp_configs.py b/pleskdistup/common/src/leapp_configs.py
index 511416c..0182668 100644
--- a/pleskdistup/common/src/leapp_configs.py
+++ b/pleskdistup/common/src/leapp_configs.py
@@ -48,13 +48,13 @@ def _do_replacement(
 
 def _do_id_replacement(id: typing.Optional[str]) -> typing.Optional[str]:
     return _do_replacement(id, [
-        lambda to_change: "alma-" + to_change,
+        lambda to_change: "alma-" + to_change if not to_change.startswith("alma-") else to_change,
     ])
 
 
 def _do_name_replacement(name: typing.Optional[str]) -> typing.Optional[str]:
     return _do_replacement(name, [
-        lambda to_change: "Alma " + to_change,
+        lambda to_change: "Alma " + to_change if not to_change.startswith("Alma ") else to_change,
         lambda to_change: to_change.replace("Enterprise Linux 7",  "Enterprise Linux 8"),
         lambda to_change: to_change.replace("EPEL-7", "EPEL-8"),
         lambda to_change: to_change.replace("$releasever", "8"),
diff --git a/pleskdistup/common/tests/leapp_configs_tests.py b/pleskdistup/common/tests/leapp_configs_tests.py
index 1f602ec..43247cb 100644
--- a/pleskdistup/common/tests/leapp_configs_tests.py
+++ b/pleskdistup/common/tests/leapp_configs_tests.py
@@ -478,6 +478,26 @@ def test_rackspace_mapping(self):
         self._perform_test({"mariadb.repo": mariadb_like_repos},
                            expected_mariadb_repos, expected_mariadb_mapping)
 
+    def test_avoid_duplicated_prefixes(self):
+        prefixed_repo = """[alma-repo1]
+name=Alma repo1
+baseurl=http://repo1/rpm-CentOS-7
+enabled=1
+gpgcheck=0
+"""
+
+        expected_leapp_repos = """[alma-repo1]
+name=Alma repo1
+baseurl=http://repo1/rpm-RedHat-el8
+enabled=1
+gpgcheck=0
+"""
+
+        expected_leapp_mapping = """alma-repo1,alma-repo1,alma-repo1,all,all,x86_64,rpm,ga,ga
+"""
+
+        self._perform_test({"prefixed.repo": prefixed_repo}, expected_leapp_repos, expected_leapp_mapping)
+
 
 class SetPackageRepositoryTests(unittest.TestCase):
     INITIAL_JSON = {