The question this page answers

Let me into Tightly, with my email and password or with the Google or Microsoft account I already use, and put me back where I was going.

What you see

Sign in, on the email step, marked 1 to 2.

1. 1Continue takes the email to the password step.
2. 2The two provider doors, Continue with Google and Continue with Microsoft.

The title is

Sign in to Tightly

with no basis line and no as-of, because nothing here is measured. A sentence sits under the title only when there is a fact to state, one at a time:

Signing you in with {provider}…

while a provider is answering, with the form and both doors disabled;

Your session expired; sign in again to continue to {destination}.

or, with nowhere remembered, Your session expired; sign in again; and

Sign in to continue to {destination}.

where the address you were opening is remembered. The destination is the page's own name, Purchase orders for instance, never a path. At rest the title stands alone.

The form is two steps. First the email, with Continue and, under the word or, the two doors Continue with Google and Continue with Microsoft. Then the password, with your address echoed in ink and Change beside it, Show or Hide as words, Sign in disabled until both fields pass, and the door Forgot password?. A Privacy policy door sits at the foot. There is no sign-up door: an account is made from an invitation or a store install, never from this page.

What to do

1. Type your email and press Continue.
2. Type your password and press Sign in; Enter does the same on either field.
3. Press Change to go back to the email step with what you typed kept.
4. Or, instead of a password, press Continue with Google or Continue with Microsoft and finish on that provider's own screen.
5. Press Forgot password? if you cannot remember your password.
6. Press Privacy policy to read it before signing in.

After a successful sign-in the frame decides where you land: a staff seat on its own portal, a new organisation in Setup at its saved step, a buyer seat in the buyer portal, everyone else at the page you were going to, or Home.

When it is empty or failed

A refusal is a line under the control it names, in ink, in the server's own words:

The provided login credentials are invalid.

for an unknown email and a wrong password alike; the server never says which. Ten wrong passwords in a row lock the account for fifteen minutes, and the refusal then says how long is left:

Too many failed sign-ins. Try again in {minutes} minutes.

An account an admin switched off reads

This account has been deactivated; ask an admin at your organisation to turn it back on.

and an address never confirmed reads

Your email address is not confirmed yet.

which returns you to the email step and offers Send the activation email again; a sent email reads back as the address it went to. A provider's refusal prints under the two doors:

Tightly signs in Google Workspace accounts. Use your work address.

Where nothing was served, the page's one client sentence stands:

Tightly could not sign you in; try again.

A resend that failed reads that the activation email could not be sent, and offers the door again. Editing the field a refusal names clears it.