Just import another key:
iason:[nous]:/tmp% gpg --search-key [email protected]
gpg: data source: https://185.125.188.26:443
(1) Christos Nouskas (Artix Master Key) <[email protected]>
4096 bit RSA key EA690BC73A4F1094, created: 2017-08-05
(2) Christos Nouskas <[email protected]>
4096 bit RSA key 606520ACB886B428, created: 2020-04-19
(3) Christos Nouskas (nous) <[email protected]>
2048 bit RSA key 6023C3BEEAB08C4A, created: 2016-09-18
(4) Christos Nouskas (nous) <[email protected]>
Christos Nouskas (nous) <[email protected]>
4096 bit RSA key FD87866ED342480C, created: 2012-03-28
(5) Christos Nouskas (mobile) <[email protected]>
3072 bit RSA key 933B32E43CC4B8FF, created: 2020-05-24
Keys 1-5 of 5 for "[email protected]". Enter number(s), N)ext, or Q)uit > 2
gpg: key 606520ACB886B428: public key "Christos Nouskas <[email protected]>" imported
gpg: Total number processed: 1
gpg: imported: 1
iason:[nous]:/tmp% gpg --encrypt --armor --recipient [email protected] file.txt
gpg: error retrieving '[email protected]' via Local: Unusable public key
gpg: error retrieving '[email protected]' via WKD: No data
gpg: [email protected]: skipped: No data
gpg: file.txt: encryption failed: No data
iason:[nous]:/tmp% gpg --search-key [email protected]
gpg: data source: https://185.125.188.26:443
(1) Christos Nouskas (Artix Master Key) <[email protected]>
4096 bit RSA key EA690BC73A4F1094, created: 2017-08-05
(2) Christos Nouskas <[email protected]>
4096 bit RSA key 606520ACB886B428, created: 2020-04-19
(3) Christos Nouskas (nous) <[email protected]>
2048 bit RSA key 6023C3BEEAB08C4A, created: 2016-09-18
(4) Christos Nouskas (nous) <[email protected]>
Christos Nouskas (nous) <[email protected]>
4096 bit RSA key FD87866ED342480C, created: 2012-03-28
(5) Christos Nouskas (mobile) <[email protected]>
3072 bit RSA key 933B32E43CC4B8FF, created: 2020-05-24
Keys 1-5 of 5 for "[email protected]". Enter number(s), N)ext, or Q)uit > 3
gpg: key 6023C3BEEAB08C4A: public key "Christos Nouskas (nous) <[email protected]>" imported
gpg: Total number processed: 1
gpg: imported: 1
iason:[nous]:/tmp% gpg --encrypt --armor --recipient [email protected] file.txt
gpg: 12A9FC955785B562: There is no assurance this key belongs to the named user
sub rsa2048/12A9FC955785B562 2016-09-18 Christos Nouskas (nous) <[email protected]>
Primary key fingerprint: 98AE 6E32 AE0A 4D12 6EAC AC8C 6023 C3BE EAB0 8C4A
Subkey fingerprint: EEC2 BDD7 73E5 7BBB CB7E A61D 12A9 FC95 5785 B562
It is NOT certain that the key belongs to the person named
in the user ID. If you *really* know what you are doing,
you may answer the next question with yes.
Use this key anyway? (y/N) y