diff --git a/Telegram/Resources/langs/lang.strings b/Telegram/Resources/langs/lang.strings
index 93e381497..d70be69c6 100644
--- a/Telegram/Resources/langs/lang.strings
+++ b/Telegram/Resources/langs/lang.strings
@@ -411,6 +411,8 @@ https://github.com/telegramdesktop/tdesktop/blob/master/LEGAL
 "lng_usernames_active" = "active";
 "lng_usernames_non_active" = "non active";
 "lng_usernames_subtitle" = "Usernames order";
+"lng_usernames_activate_error#one" = "Sorry, you can't activate more than **{count}** usernames.";
+"lng_usernames_activate_error#other" = "Sorry, you can't activate more than **{count}** usernames.";
 "lng_usernames_activate_description" = "Do you want to show this username on your info page?";
 "lng_usernames_activate_confirm" = "Show";
 "lng_channel_usernames_subtitle" = "Links order";
diff --git a/Telegram/SourceFiles/api/api_user_names.cpp b/Telegram/SourceFiles/api/api_user_names.cpp
index 67f5a31e9..3e74dd65c 100644
--- a/Telegram/SourceFiles/api/api_user_names.cpp
+++ b/Telegram/SourceFiles/api/api_user_names.cpp
@@ -98,7 +98,7 @@ rpl::producer<Data::Usernames> Usernames::loadUsernames(
 	};
 }
 
-rpl::producer<> Usernames::toggle(
+rpl::producer<rpl::no_value, Usernames::Error> Usernames::toggle(
 		not_null<PeerData*> peer,
 		const QString &username,
 		bool active) {
@@ -118,31 +118,47 @@ rpl::producer<> Usernames::toggle(
 		entry.usernames.push_back(username);
 	}
 
-	const auto finish = [=] {
+	const auto pop = [=](Error error) {
 		const auto it = _toggleRequests.find(peerId);
 		if (it != end(_toggleRequests)) {
 			auto &list = it->second.usernames;
 			list.erase(ranges::remove(list, username), end(list));
 			if (list.empty()) {
-				it->second.done.fire_done();
+				if (error == Error::Unknown) {
+					it->second.done.fire_done();
+				} else if (error == Error::TooMuch) {
+					it->second.done.fire_error_copy(error);
+				}
 				_toggleRequests.remove(peerId);
 			}
 		}
 	};
 
+	const auto done = [=] {
+		pop(Error::Unknown);
+	};
+	const auto fail = [=](const MTP::Error &error) {
+		const auto type = error.type();
+		if (type == u"USERNAMES_ACTIVE_TOO_MUCH"_q) {
+			pop(Error::TooMuch);
+		} else {
+			pop(Error::Unknown);
+		}
+	};
+
 	if (peer->isSelf()) {
 		_api.request(MTPaccount_ToggleUsername(
 			MTP_string(username),
 			MTP_bool(active)
-		)).done(finish).fail(finish).send();
+		)).done(done).fail(fail).send();
 	} else if (const auto channel = peer->asChannel()) {
 		_api.request(MTPchannels_ToggleUsername(
 			channel->inputChannel,
 			MTP_string(username),
 			MTP_bool(active)
-		)).done(finish).fail(finish).send();
+		)).done(done).fail(fail).send();
 	} else {
-		return rpl::never<>();
+		return rpl::never<rpl::no_value, Error>();
 	}
 	return entry.done.events();
 }
diff --git a/Telegram/SourceFiles/api/api_user_names.h b/Telegram/SourceFiles/api/api_user_names.h
index d94ecdc95..54b59ac29 100644
--- a/Telegram/SourceFiles/api/api_user_names.h
+++ b/Telegram/SourceFiles/api/api_user_names.h
@@ -21,11 +21,16 @@ namespace Api {
 
 class Usernames final {
 public:
+	enum class Error {
+		TooMuch,
+		Unknown,
+	};
+
 	explicit Usernames(not_null<ApiWrap*> api);
 
 	[[nodiscard]] rpl::producer<Data::Usernames> loadUsernames(
 		not_null<PeerData*> peer) const;
-	[[nodiscard]] rpl::producer<> toggle(
+	[[nodiscard]] rpl::producer<rpl::no_value, Error> toggle(
 		not_null<PeerData*> peer,
 		const QString &username,
 		bool active);
@@ -45,7 +50,7 @@ private:
 
 	using Key = PeerId;
 	struct Entry final {
-		rpl::event_stream<> done;
+		rpl::event_stream<rpl::no_value, Error> done;
 		std::vector<QString> usernames;
 	};
 	base::flat_map<Key, Entry> _toggleRequests;
diff --git a/Telegram/SourceFiles/boxes/peers/edit_peer_usernames_list.cpp b/Telegram/SourceFiles/boxes/peers/edit_peer_usernames_list.cpp
index e775e7bc0..2c785024d 100644
--- a/Telegram/SourceFiles/boxes/peers/edit_peer_usernames_list.cpp
+++ b/Telegram/SourceFiles/boxes/peers/edit_peer_usernames_list.cpp
@@ -17,6 +17,7 @@ https://github.com/telegramdesktop/tdesktop/blob/master/LEGAL
 #include "ui/boxes/confirm_box.h"
 #include "ui/layers/show.h"
 #include "ui/painter.h"
+#include "ui/text/text_utilities.h" // Ui::Text::RichLangValue.
 #include "ui/toast/toast.h"
 #include "ui/widgets/buttons.h"
 #include "ui/widgets/popup_menu.h"
@@ -283,8 +284,23 @@ void UsernamesList::rebuild(const Data::Usernames &usernames) {
 							_peer,
 							username.username,
 							!username.active
-						) | rpl::start_with_done([=] {
+						) | rpl::start_with_error_done([=](
+								Api::Usernames::Error error) {
+							if (error == Api::Usernames::Error::TooMuch) {
+								constexpr auto kMaxUsernames = 10.;
+								_show->showBox(
+									Ui::MakeInformBox(
+										tr::lng_usernames_activate_error(
+											lt_count,
+											rpl::single(kMaxUsernames),
+											Ui::Text::RichLangValue)),
+									Ui::LayerOption::KeepOther);
+							}
 							load();
+							_toggleLifetime.destroy();
+						}, [=] {
+							load();
+							_toggleLifetime.destroy();
 						});
 					});
 					close();