itsIt's not a new issue. iI just faced such a problem and mostly thatsthat's because unityUnity and vsVS or other IDEIDEs are not synced. sometimes eventSometimes even going to preferencesPreferences and setting the chosen IDE even doesntdoesn't work. c#C# classes are known as miscellaneous and auto-complete cantcan't find the right choices.
sometimes itsSometimes it's because you use a cracked version of vsVS or unityUnity or just downloaddownloaded them from un-officialan unofficial source.
mostMost of the time iI choose the last solution first. justJust remove both vsVS and unityUnity and download them from their official website. fromFrom the time i useI used official versions iI just dontdon't face such problems.
