Cannot verify 4.26 with GPG - No public key error

I've been verifying releases via GPG for a long time now.

4.25 verifies successfully:

$ TZ=UTC gpg --no-options --keyid-format long --verify tails-amd64-4.25.iso.sig tails-amd64-4.25.iso
gpg: Signature made Mon 06 Dec 2021 16:19:27 UTC
gpg:                using RSA key 05469FB85EAD6589B43D41D3D21DAD38AF281C0B
gpg: checking the trustdb
gpg: marginals needed: 3  completes needed: 1  trust model: pgp
gpg: depth: 0  valid:   2  signed:   4  trust: 0-, 0q, 0n, 0m, 0f, 2u
gpg: depth: 1  valid:   4  signed: 137  trust: 0-, 0q, 0n, 4m, 0f, 0u
gpg: depth: 2  valid:   3  signed: 128  trust: 3-, 0q, 0n, 0m, 0f, 0u
gpg: next trustdb check due at 2022-01-16
gpg: Good signature from "Tails developers (offline long-term identity key) <tails@boum.org>" [full]
gpg:                 aka "Tails developers <tails@boum.org>" [full]

4.26 does not:

$ TZ=UTC gpg --no-options --keyid-format long --verify tails-amd64-4.26.iso.sig tails-amd64-4.26.iso
gpg: Signature made Mon 10 Jan 2022 13:57:06 UTC
gpg:                using RSA key 753F901377A309F2731FA33F7BFBD2B902EE13D0
gpg: Can't check signature: No public key

The sha256 hash does match: b8841488be44e2503c7f190eb0a9ac21b75969067824585d1f4f1060143ea2e3

??