message: start transaction - check for issuer flag on authorize
diff: @@ -1875,6 +1875,10 @@ export default class OCPPUtils {
  }
  public static async checkBillingPrerequisites(tenant: Tenant, chargingStation: ChargingStation, user: User): Promise<void> {
  + if (!user.issuer) {
  + // Roaming - do not check for payment methods
  + return;
  + }
  const billingImpl = await BillingFactory.getBillingImpl(tenant);
  if (billingImpl) {
  const errorCodes = await billingImpl.precheckStartTransactionPrerequisites(user);
  