@Robert Lescault Welcome to Microsoft Q&A, Thank you for posting your here!!
From the error message we could see it is permission issue on the Storage account you need to add a role assignment to the user. Please go to Storage account -> Access Control -> Add -> Add role assignment, then add Storage Blob Data Owner to your login account and the try to upload the file to the Storage account without using the SAS token.
azcopy login --tenant-id "abcdefg-1234-5678-adgj-12ed456gyh"
azcopy copy 'C:\LocalFolder\LocalFile.txt' 'https://myStorageAccount.blob.core.windows.net/myBLOBcontainer'
If you'd rather use a SAS token to authorize access to blob data, then you can append that token to the resource URL in each Az Copy command.
For example: azcopy copy "/path/to/file.txt" "https://[account].blob.core.windows.net/[container]/[path/to/blob]?[SAS]"
Reference Article: https://learn.microsoft.com/en-us/azure/storage/common/storage-use-azcopy-blobs-upload#get-started
Hope this helps!
Kindly let us know if the above helps or you need further assistance on this issue.
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