It seems that your field value APR-2644 is being interpreted as a date by Excel because it matches the format of “mmm-yyyy”.
To prevent this, you can try one of these methods:
Add an apostrophe (') before the text value, e.g., 'APR-2644
Format the cell as text before entering or pasting the value
Use the TEXT function to convert the value to text,
Use the DATEVALUE function to convert the text value to a serial number and then apply a date format
I hope this helps.