Hi @Shiva narayana Chintala ,
I understand that you are a site administrator, but when you edit home page, format text options are grayed out.
I found a thread with the same problem as yours:https://answers.microsoft.com/en-us/msoffice/forum/all/sharepoint-online-2016-edit-page-is-grayed-out/a293ba14-df8d-472c-9e20-3025313c3991
It is hard to troubleshot this issue via community, we suggest you open a ticket from Microsoft for further help.
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