Excel files not opening suddenly

Out of the blue, most of my Excel files are not opening. The application itself is opening, but most of the files do not (some, very few, do however). Here is the picture of what the application tells me:

When I click on "More Information" button, I get a long list of messages, some of which from the top I am enclosing here. They go for many more pages, from Thread 0 to Thread 26 and then some more messages indicating what libraries were open, and then a couple of "closing paragraphs". I have no idea what to do with it. Can someone help please!

"Microsoft Error Reporting log version: 2.0

Error Signature:

Exception: EXC_BAD_ACCESS

ExceptionEnumString: 1

Exception Code: KERN_INVALID_ADDRESS (0x0000000000000000)

Date/Time: 2022-01-29 23:37:54 +0000

Application Name: Microsoft Excel

Application Bundle ID: com.microsoft.Excel

Application Signature: XCEL

Application Bitness: x64

Application Version: 16.53.0.21091200

Crashed Module Name: CoreFoundation

Crashed Module Version: 1774.101

Crashed Module Offset: 0x0000000000007b44

Blame Module Name: MicrosoftFontLibrary

Blame Module Version: 16.53.21091200

UnsymbolicatedChecksum: 2B63587A7C14175D3C12831AD03ADF64

Blame Module Offset: 0x000000000001a0f4

StackHash: f1f76fb5874cacf2-dm_1_main_arm

Application LCID: 1033

Extra app info: Reg=en Loc=0x0409

Build Type: Release

Crashed thread Stack Pointer: 0x_000000016d7a9d00

Crashed thread: 0

Thread 0 crashed (0x54a0):

# 1 0x0000000191af0b44 in _CFDictionaryGetValue + 0x00000064 (CoreFoundation + 0x0000000000007b44) 0x0000000000000000

# 2 0x0000000105e6e0f4 in (MicrosoftFontLibrary + 0x000000000001a0f4) 0x0000000000000000

# 3 ...

... ...

OS Information

Operating System: Mac OS X 11.2.3 (Build 20D91)

CPU: ARM64e, Logical CPU Count: 8

Physical Memory: 8192 MB

Device_model: MacBookPro17,1

Screen: 1440.000000 x 900.000000, bitsPerPixel = 24, frame = 0.000000, 0.000000, 1440.000000, 900.000000

CrashedApp_Virtual_Memory_Size_MB: 402129.000000

CrashedApp_Resident_Memory_Size_MB: 418.000000

CrashedApp_Memory_Footprint_MB: 236.000000

ErrorReportingDeviceUUID: 0A789AD4-BA3D-5DD4-9665-5CFB25711222

ErrorReportingUUID: 6E06DD0E-377D-421F-B488-0FE5E7375E75

ULS UUID: B9A72632-9E24-4E44-B890-A06F41C606F1

CrashedLogSessionId: B9A72632-9E24-4E44-B890-A06F41C606F1

TimeFromLaunch: 0 hours, 0 minutes, 41 seconds

CrashedSessionDuration: 41

Total errors on this client: 28

Microsoft Application Information:

Tenant_Id: 6c4d949d-b91c-4c45-9aae-66d76443110d

Audience: Production

SHSuffixKey_0: _arm

AudienceChannel: CC

AudienceGroup: Production"