If you're playing on pc, follow these steps:
1. Press the windows button and R at the same time and you will see a run dialogue box
2. Type %appdata%\StardewValley\Saves
3. Click "OK" to open the Saves folder
4. Click the folder with your farm name on it
5. Open the file in the folder with your farm name on it with Notepad
6. Click Edit and then click Find
7. Search "uiScale" and then replace the numbers next to it with 1
8. Click File and then click Save
Check your game to see if it works