@txtnlrn,asks,@zohosheet, how long does it take to open a shared #zohosheet?

@txtnlrn,asks,@zohosheet, how long does it take to open a shared #zohosheet?

Hello,
Scenario:
I shared a Zohosheet with my customer.
Gave him the access writes to read and write.
When he tried to access the zohosheet it opened as a read only.

I tried to assist. I set another email address of my to share the same zohosheet.
Logged in with that email address. Clicked on the zohosheet and the system kept displaying loading or generating ... filename.

What did I miss?

Thank you
Staff TXTNLRN
@TXTNLRN