zero instead of #value! in cells operating text with text and text with numbers

Greetings, I need collaboration to unveil the formatting of a spreadsheet. A contractor sent a workbook which contains a worksheet with a formatting that yields zero values in all cells instead of #value! error when multiplying or otherwise operating with cells containing text with others also containing text. The same situation applies when the worksheet is requested to operate text and numbers. And those cells show blank on the screen but keep the formulas. No special formulas to hide #value! errors are being used.

When copying the mentioned worksheet to another empty worksheet in the same workbook, the #value! error appears.

Please find attached this example showing the situation.

Thanks for the assistance.