Make Events payment routing plan-aware.

Co-authored-by: Cursor <cursoragent@cursor.com>

app/Services/Payments/MerchantGatewayService.php

@@ -19,11 +19,13 @@ class MerchantGatewayService
 
     public function isConfigured(User|string $owner): bool
     {
-        if (! $this->ownerMayUseGateway($owner)) {
-            return false;
-        }
+        return $this->shouldUseOwnerGateway($owner);
+    }
 
-        return (bool) $this->settingFor($owner)?->isConfigured();
+    public function shouldUseOwnerGateway(User|string $owner): bool
+    {
+        return $this->ownerMayUseGateway($owner)
+            && (bool) $this->settingFor($owner)?->isConfigured();
     }
 
     /**
@@ -55,7 +57,12 @@ class MerchantGatewayService
      */
     public function verify(User|string $owner, string $reference): array
     {
-        $setting = $this->requireConfigured($owner);
+        // Do not re-check the current plan here: an owner-gateway payment
+        // initiated before a downgrade must remain verifiable.
+        $setting = $this->settingFor($owner);
+        if (! $setting?->isConfigured()) {
+            throw new RuntimeException('The payment gateway used for this transaction is no longer configured.');
+        }
 
         return match ($setting->provider) {
             PaymentGatewaySetting::PROVIDER_PAYSTACK => $this->paystackVerify($setting, $reference),