Yes, it is to late to file an extension request electronically, as stated by the IRS.
https://www.irs.gov/forms-pubs/extension-of-time-to-file-your-tax-return
Victims in FEMA Disaster Areas: Mail Your Request for an Extension of Time to File
To request an extension to file your federal taxes after May 17, 2021, print and mail Form 4868, Application for Automatic Extension of Time To File U.S. Individual Income Tax Return. We can’t process extension requests filed electronically after May 17, 2021.
Find out where to mail your form.
