Je crois you are experiencing one du Auto-Correct fonctionnalités of Microsoft Office applications, which tries to assume that you've got the CAPS LOCK clé on when vous n'avez pas en fait want it to be on.
Parce que il y a so many different versions of Office, where you change this actual setting may be different - but, par exemple, in Microsoft 365 Apps for Business, Excel Version 2507 (Build 19029.20184 Click-to-Run) I trouvez le setting by going to:
Fichier -> Options (bottom left-hand corner du écran), the "Excel Options" pop-up window will appear.
Withdans le "Excel Options" window, allez à "Proofing", ensuite click sur le "AutoCorrect Options..." bouton. In there vous allez see a setting called "Correct accidental use of cAPS lOCK clé". Turn that setting off (ie. untick it), and ensuite vous devriez trouvez le behaviour you were experiencing ne devrait pas occur anymore.
(Of course, if vous êtes ensuite doing other things within Excel, Word, or other Office apps, and you really do accidentally have the CAPS LOCK clé on, ensuite c'est not going to try and "fix" that for you)