diff --git a/app/telegram/functions/main_settings/settings.py b/app/telegram/functions/main_settings/settings.py
index 92ee946..df7e2c3 100644
--- a/app/telegram/functions/main_settings/settings.py
+++ b/app/telegram/functions/main_settings/settings.py
@@ -15,6 +15,34 @@ logger = logging.getLogger("main_settings")
 router_main_settings = Router()
 
 
+def is_number(value: str) -> bool:
+    """
+    Checks if a given string represents a number.
+
+    Args:
+        value (str): The string to check.
+
+    Returns:
+        bool: True if the string represents a number, False otherwise.
+    """
+    try:
+        # Convert the string to a float
+        num = float(value)
+        # Check if the number is positive
+        if num <= 0:
+            return False
+        # Check if the string contains "+" or "-"
+        if "+" in value or "-" in value:
+            return False
+        # Check if the string contains only digits
+        allowed_chars = set("0123456789.")
+        if not all(ch in allowed_chars for ch in value):
+            return False
+        return True
+    except ValueError:
+        return False
+
+
 async def reg_new_user_default_main_settings(id, message):
     tg_id = id
 
@@ -124,7 +152,6 @@ async def state_trading_mode(callback: CallbackQuery, state):
         logger.error("Ошибка при обновлении режима торговли: %s", e)
 
 
-
 async def switch_mode_enabled_message(message, state):
     await state.set_state(update_main_settings.switch_mode_enabled)
 
@@ -304,7 +331,7 @@ async def state_starting_quantity(message: Message, state):
     data = await state.get_data()
     data_settings = await rq.get_user_main_settings(message.from_user.id)
 
-    if data['starting_quantity'].isdigit():
+    if is_number(data['starting_quantity']):
         await message.answer(f"✅ Изменено: {data_settings['starting_quantity']} → {data['starting_quantity']}")
 
         await rq.update_starting_quantity(message.from_user.id, data['starting_quantity'])
@@ -345,4 +372,4 @@ async def state_maximal_quantity(message: Message, state):
             f'⛔️ Ошибка: ваше значение ({val}) или выше лимита (100) или вы вводите неверные символы')
         logger.error(f'⛔️ Ошибка: ваше значение ({val}) или выше лимита (100) или вы вводите неверные символы')
 
-        await main_settings_message(message.from_user.id, message)
\ No newline at end of file
+        await main_settings_message(message.from_user.id, message)