It looks like you've entered a reference error, which is common in spreadsheet applications like Microsoft Excel or Google Sheets. This error typically occurs when a formula refers to a cell that is not valid, often because the cell has been deleted or the reference is incorrect.

Here are a few steps to troubleshoot and resolve a #REF! error:

1. **Check Deleted Cells**: Ensure that the cells your formula refers to have not been deleted. If they have, you will need to adjust the formula to refer to the correct cells.

2. **Correct Cell References**: Double-check the cell references in your formula. Make sure they are correct and within the valid range of your spreadsheet.

3. **Adjust Formula**: If you have moved or copied the formula, ensure that the relative and absolute references are correct. Use `$` to fix a reference if needed.

4. **Circular References**: Ensure that your formula does not create a circular reference, where a formula refers back to its own cell either directly or indirectly.

5. **Check for Merged Cells**: If your formula references a range that includes merged cells, ensure that the reference is correct and that the merged cells are not causing the issue.

If you provide more context or details about the specific formula or situation, I can offer more targeted advice.