The EOSinfo does not support your new t7i, you can see your t7i is not in the support list.
http
/astrojargon.net/eosinfo.aspx?AspxAutoDetectCookieSupport=1
The EOSmsg should be fine, but I don't know why you can't get the shutter count, maybe the software has bug for the new model, eg for your t7i.
http
/www.eosmsg.com/#model
And the newer version, ShutterCount 3.3 is for MAC only, if you have iphone or ipad, just try it. https

/www.direstudio.com/shuttercount/ Here is the support camera list: https

/www.direstudio.com/shuttercount/tech-specs/
Here is the ShutterCount 3.3 https

/www.direstudio.com/shuttercount/
Or try this online
shutter counter for check the shutter count, keep in mind it may or may not work. https

/shuttercounter.com/