-----BEGIN BITCOIN SIGNED MESSAGE-----
Date: 10/05/2021
This is the real owner of the bitcointalk account :Martin958
My bitcointalk profile is: https://bitcointalk.org/index.php?action=profile;u=314728
-----BEGIN SIGNATURE-----
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Hy/9LCwYkEZ894Wr539+SftgMM7KmxVgFOrTP5Q3ypizI1yov4Hwbcgoiblpn089O1hGfNKUA2CLzGsG7j3Ght8=
-----END BITCOIN SIGNED MESSAGE-----
Date: 10/05/2021
This is the real owner of the bitcointalk account :Martin958
My bitcointalk profile is: https://bitcointalk.org/index.php?action=profile;u=314728
-----BEGIN SIGNATURE-----
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-----END BITCOIN SIGNED MESSAGE-----
I'm not able to verify using Electrum. (i tried several times, maybe you've done a bad copy/paste ?)
It says the request expires in about 24 hours. Does that have anything to do with it? I don't think the copy/paste was wrong.