Pull ingest gets no signal despite a valid SRT URL

I'm testing the stream setup for the upcoming season. I scheduled two recordings receiving signal from our broadcaster through an SRT link, but although the recording was scheduled to start, I'm still not getting any image.

Test the pull URL in a player to check whether any signal arrives.
- How to check a live ingest signal in VLC?
If the player gets no signal either, check whether the SRT source is actually encrypted — a passphrase in the pull URL is rejected when the source stream is unencrypted.
Remove the ?passphrase=... parameter from the pull URL.
Alternatively, to keep encryption, ask the source to enable AES with that passphrase on the encoder so the existing URL works as-is.
Recreate the live schedule with the corrected URL.
- How to recreate a live schedule?

An SRT connection fails when the encryption settings on the pull URL and the source do not match. Sending a passphrase to an unencrypted source rejects the handshake, so no feed arrives even though the source is reachable.