What should I do now?

Had a job interview last night the interview went great and they told me i got the job but they said give them an hour to send my offer letter. I waited for two hours and called them back and they told me to update my portal and they’d send it within 5 minutes.

Here it is the next day and still no offer letter i called up there twice and either no one is answering or I’m left on hold for more than 30 minutes
What should I do now?
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