Did you try to go to go to Settings then click Account while using the phone? The free trial request should be there.
If that doesn't work get in touch with contact customer support through this link:
https://support.spotify.com/contact-spotify-support/
They'll help you out. They take, at the most, 24 hrs to get back to you.
Hey there you, Yeah, you! 😁 Welcome - we're glad you joined the Spotify Community! While you here, let's have a fun game…
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