diff --git a/go.mod b/go.mod
index 4132199f1eb..35d86dc4984 100644
--- a/go.mod
+++ b/go.mod
@@ -309,7 +309,7 @@ replace github.com/opentracing-contrib/go-stdlib => github.com/grafana/opentraci
 replace github.com/opentracing-contrib/go-grpc => github.com/charleskorn/go-grpc v0.0.0-20231024023642-e9298576254f
 
 // Replacing prometheus/alertmanager with our fork.
-replace github.com/prometheus/alertmanager => github.com/grafana/prometheus-alertmanager v0.25.1-0.20240924175849-b8b7c2c74eb6
+replace github.com/prometheus/alertmanager => github.com/grafana/prometheus-alertmanager v0.25.1-0.20240930132144-b5e64e81e8d3
 
 // Replacing with a fork commit based on v1.17.1 having cherry-picked the following PRs:
 // - https://github.com/grafana/franz-go/pull/1
diff --git a/go.sum b/go.sum
index 1618943aa99..ed243096666 100644
--- a/go.sum
+++ b/go.sum
@@ -1272,8 +1272,8 @@ github.com/grafana/mimir-prometheus v0.0.0-20241003114040-35ec40c3b27a h1:Thi1mh
 github.com/grafana/mimir-prometheus v0.0.0-20241003114040-35ec40c3b27a/go.mod h1:oyDm7JaLUh+QGuGkC7iXC8IyTUq5rlh1ba2CRm9DlVg=
 github.com/grafana/opentracing-contrib-go-stdlib v0.0.0-20230509071955-f410e79da956 h1:em1oddjXL8c1tL0iFdtVtPloq2hRPen2MJQKoAWpxu0=
 github.com/grafana/opentracing-contrib-go-stdlib v0.0.0-20230509071955-f410e79da956/go.mod h1:qtI1ogk+2JhVPIXVc6q+NHziSmy2W5GbdQZFUHADCBU=
-github.com/grafana/prometheus-alertmanager v0.25.1-0.20240924175849-b8b7c2c74eb6 h1:nT8QXdJo6wHMBcF0xEoXxEWkoUZOyzV/jyi/u9l7YEk=
-github.com/grafana/prometheus-alertmanager v0.25.1-0.20240924175849-b8b7c2c74eb6/go.mod h1:YeND+6FDA7OuFgDzYODN8kfPhXLCehcpxe4T9mdnpCY=
+github.com/grafana/prometheus-alertmanager v0.25.1-0.20240930132144-b5e64e81e8d3 h1:6D2gGAwyQBElSrp3E+9lSr7k8gLuP3Aiy20rweLWeBw=
+github.com/grafana/prometheus-alertmanager v0.25.1-0.20240930132144-b5e64e81e8d3/go.mod h1:YeND+6FDA7OuFgDzYODN8kfPhXLCehcpxe4T9mdnpCY=
 github.com/grafana/pyroscope-go/godeltaprof v0.1.8 h1:iwOtYXeeVSAeYefJNaxDytgjKtUuKQbJqgAIjlnicKg=
 github.com/grafana/pyroscope-go/godeltaprof v0.1.8/go.mod h1:2+l7K7twW49Ct4wFluZD3tZ6e0SjanjcUUBPVD/UuGU=
 github.com/grafana/regexp v0.0.0-20240531075221-3685f1377d7b h1:oMAq12GxTpwo9jxbnG/M4F/HdpwbibTaVoxNA0NZprY=
diff --git a/vendor/github.com/prometheus/alertmanager/api/metrics/metrics.go b/vendor/github.com/prometheus/alertmanager/api/metrics/metrics.go
index ea45acc2ee1..2a91911c3d7 100644
--- a/vendor/github.com/prometheus/alertmanager/api/metrics/metrics.go
+++ b/vendor/github.com/prometheus/alertmanager/api/metrics/metrics.go
@@ -13,7 +13,12 @@
 
 package metrics
 
-import "github.com/prometheus/client_golang/prometheus"
+import (
+	"github.com/go-kit/log"
+	"github.com/go-kit/log/level"
+
+	"github.com/prometheus/client_golang/prometheus"
+)
 
 // Alerts stores metrics for alerts.
 type Alerts struct {
@@ -24,7 +29,7 @@ type Alerts struct {
 
 // NewAlerts returns an *Alerts struct for the given API version.
 // Since v1 was deprecated in 0.28, v2 is now hardcoded.
-func NewAlerts(r prometheus.Registerer) *Alerts {
+func NewAlerts(r prometheus.Registerer, l log.Logger) *Alerts {
 	numReceivedAlerts := prometheus.NewCounterVec(prometheus.CounterOpts{
 		Name:        "alertmanager_alerts_received_total",
 		Help:        "The total number of received alerts.",
@@ -36,7 +41,12 @@ func NewAlerts(r prometheus.Registerer) *Alerts {
 		ConstLabels: prometheus.Labels{"version": "v2"},
 	})
 	if r != nil {
-		r.MustRegister(numReceivedAlerts, numInvalidAlerts)
+		for _, c := range []prometheus.Collector{numReceivedAlerts, numInvalidAlerts} {
+			r.Unregister(c)
+			if err := r.Register(c); err != nil {
+				level.Error(l).Log("msg", "Failed to register collector", "err", err)
+			}
+		}
 	}
 	return &Alerts{
 		firing:   numReceivedAlerts.WithLabelValues("firing"),
diff --git a/vendor/github.com/prometheus/alertmanager/api/v2/api.go b/vendor/github.com/prometheus/alertmanager/api/v2/api.go
index 80babb460b3..4372309e5cf 100644
--- a/vendor/github.com/prometheus/alertmanager/api/v2/api.go
+++ b/vendor/github.com/prometheus/alertmanager/api/v2/api.go
@@ -100,7 +100,7 @@ func NewAPI(
 		peer:           peer,
 		silences:       silences,
 		logger:         l,
-		m:              metrics.NewAlerts(r),
+		m:              metrics.NewAlerts(r, l),
 		uptime:         time.Now(),
 	}
 
diff --git a/vendor/modules.txt b/vendor/modules.txt
index 2136cfaeb89..84b219ed9df 100644
--- a/vendor/modules.txt
+++ b/vendor/modules.txt
@@ -915,7 +915,7 @@ github.com/pmezard/go-difflib/difflib
 # github.com/power-devops/perfstat v0.0.0-20210106213030-5aafc221ea8c
 ## explicit; go 1.14
 github.com/power-devops/perfstat
-# github.com/prometheus/alertmanager v0.27.0 => github.com/grafana/prometheus-alertmanager v0.25.1-0.20240924175849-b8b7c2c74eb6
+# github.com/prometheus/alertmanager v0.27.0 => github.com/grafana/prometheus-alertmanager v0.25.1-0.20240930132144-b5e64e81e8d3
 ## explicit; go 1.22
 github.com/prometheus/alertmanager/api
 github.com/prometheus/alertmanager/api/metrics
@@ -1674,6 +1674,6 @@ sigs.k8s.io/yaml/goyaml.v3
 # github.com/munnerz/goautoneg => github.com/grafana/goautoneg v0.0.0-20240607115440-f335c04c58ce
 # github.com/opentracing-contrib/go-stdlib => github.com/grafana/opentracing-contrib-go-stdlib v0.0.0-20230509071955-f410e79da956
 # github.com/opentracing-contrib/go-grpc => github.com/charleskorn/go-grpc v0.0.0-20231024023642-e9298576254f
-# github.com/prometheus/alertmanager => github.com/grafana/prometheus-alertmanager v0.25.1-0.20240924175849-b8b7c2c74eb6
+# github.com/prometheus/alertmanager => github.com/grafana/prometheus-alertmanager v0.25.1-0.20240930132144-b5e64e81e8d3
 # github.com/twmb/franz-go => github.com/grafana/franz-go v0.0.0-20241009101240-fa97d35e871f
 # google.golang.org/grpc => google.golang.org/grpc v1.65.0