Hi @Steven Ma
As your issue is related to Excel for web, I suggest you post a new thread on Microsoft Answers Community ---Microsoft 365 and Office.
I personally suggest you user other browser for a test, such as Edge. If this issue still reproduced on Edge, please click the Windows Security Center icon in the taskbar - Applications and browser controls - Reputation-based protection settings - (temporarily) uncheck "SmartScreen for Microsoft Edge".
Then check the anti-virus software settings if there is.
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