Spreadsheet: changing cell font style "normal"

Desktop editors
1

Do you want to: Ask a how-to question

OS version: Macbook Pro, IOS Sequoia 15.7.2
App version: Desktop 9.3.1
Downloaded from: ONLYOFFICE website
Additional information:

I have created a standard template, where the font of all cell’s was change to Helvetica, but as soon as I merge two cell, the cont was change to Calibri. It seems that the styles ie. “normal”, “netral” etc. etc. was not change to Helvetica.

Question: How do I change the default style?

Thank you from a newbee