Answer:
a. What do you do?
First, try to understand her perspective and ask her why she hasn't shared the spreadsheet. Maybe there is a valid reason for it. If she doesn't provide a satisfactory response and continues to withhold the spreadsheet, it is important to escalate the issue to a supervisor or manager. Explain the situation to them and ask for their intervention. It is important to stress the significance of having access to the spreadsheet for the smooth functioning of the company's inventory management. Documenting the issue and all communication with the co-worker can also be helpful.
b. How do you handle this when she states she will do it again and doesn’t share the sheet?
If the co-worker continues to refuse to share the spreadsheet, despite your efforts to resolve the issue, it is important to escalate it to the next level of management. It may also be helpful to have a meeting with the co-worker and the supervisor to discuss the situation and find a mutually agreeable solution. If the co-worker's behavior is affecting the company's productivity, it may be necessary for the management to take disciplinary action against her. However, it is important to approach the situation with professionalism and diplomacy and avoid personal attacks or confrontations.