diff --git a/internal/services/configstore/api/client.go b/internal/services/configstore/api/client.go
index 781057e..70482d6 100644
--- a/internal/services/configstore/api/client.go
+++ b/internal/services/configstore/api/client.go
@@ -31,7 +31,7 @@ import (
 	"github.com/pkg/errors"
 )
 
-var jsonContent = http.Header{"content-type": []string{"application/json"}}
+var jsonContent = http.Header{"Content-Type": []string{"application/json"}}
 
 // Client represents a Gogs API client.
 type Client struct {
diff --git a/internal/services/gateway/api/client.go b/internal/services/gateway/api/client.go
index 3b26dee..e4ff720 100644
--- a/internal/services/gateway/api/client.go
+++ b/internal/services/gateway/api/client.go
@@ -30,7 +30,7 @@ import (
 	"github.com/pkg/errors"
 )
 
-var jsonContent = http.Header{"content-type": []string{"application/json"}}
+var jsonContent = http.Header{"Content-Type": []string{"application/json"}}
 
 // Client represents a Gogs API client.
 type Client struct {
diff --git a/internal/services/runservice/scheduler/api/client.go b/internal/services/runservice/scheduler/api/client.go
index e5aa0e8..7c55b3b 100644
--- a/internal/services/runservice/scheduler/api/client.go
+++ b/internal/services/runservice/scheduler/api/client.go
@@ -30,7 +30,7 @@ import (
 	rstypes "github.com/sorintlab/agola/internal/services/runservice/types"
 )
 
-var jsonContent = http.Header{"content-type": []string{"application/json"}}
+var jsonContent = http.Header{"Content-Type": []string{"application/json"}}
 
 // Client represents a Gogs API client.
 type Client struct {