diff --git a/locale/fy_NL/settings.ftl b/locale/fy_NL/settings.ftl
index 0b7a5c3d96..8fbe8f6bed 100644
--- a/locale/fy_NL/settings.ftl
+++ b/locale/fy_NL/settings.ftl
@@ -992,6 +992,12 @@ tfa-row-backup-phone-delete-button = Fuortsmite
 # Shown in tooltip on delete button or delete icon
 tfa-row-backup-phone-delete-title = Reserve-wersteltelefoan fuortsmite
 tfa-row-backup-phone-delete-restriction = As jo jo reserve-wersteltelefoan fuortsmite wolle, foegje dan earst reserve-autentikaasjekoaden ta of skeakelje earst twastapsautentikaasje út om foar te kommen dat jo gjin tagong mear hawwe ta jo account.
+# "this" refers to backup recovery phone
+tfa-row-backup-phone-description = Dit is de ienfâldigere werstelmetoade as jo jo autentikaasje-app net brûke kinne.
+# A SIM swap attack is a type of identity theft where an attacker tricks or bribes a mobile carrier
+# into transferring a victim's phone number to their own SIM card, enabling access to accounts secured
+# with SMS-based two-factor authentication.
+tfa-row-backup-phone-sim-swap-risk-link = Mear ynfo oer it risiko fan simkaartwikseling
 
 ## Switch component
 
@@ -1153,6 +1159,7 @@ auth-error-1010 = Jildich wachtwurd fereaske
 auth-error-1011 = Jildich e-mailadres fereaske
 auth-error-1031 = Jo moatte jo leeftiid ynfiere om te registrearjen
 auth-error-1032 = Jo moatte in jildige leeftiid ynfiere om te registrearjen
+auth-error-1054 = Unjildige koade foar autentikaasje yn twa stappen
 auth-error-1062 = Unjildige trochferwizing
 oauth-error-1000 = Der is wat misgien. Slút dit ljepblêd en probearje it opnij.
 
@@ -1633,6 +1640,7 @@ signin-token-code-instruction-desktop-relay = { -brand-firefox } probearret jo w
 ## TOTP (time-based one-time password) is a form of two-factor authentication (2FA).
 ## Users that have set up two-factor authentication land on this page during sign-in.
 
+signin-totp-code-header = Oanmelde
 signin-totp-code-subheader-v2 = Fier twastaps-autentikaasjekoade yn
 signin-totp-code-instruction-v4 = Kontrolearje jo <strong>autentikaasje-app</strong> om jo oanmelding te befêstigjen.
 signin-totp-code-input-label-v4 = Fier 6-siferige koade yn