[Solved] typescript method returning undefined?
Rewrite your getCampaignsToClone method so it returns an Observable sequence. Use flatMap to subscribe to the getUnpaginatedCampaigns observable in turn. getCampaignsToClone(flight: Flight): Observable<CampaignUnpaginated[]> { return this.campaignService.getStatuses().pipe( map(data => data.filter( x => x.code === (CampaignStatusCode.IN_PROGRESS || CampaignStatusCode.READY)).map(x => x.id)), flatMap(ids => this.campaignService.getUnpaginatedCampaigns({ statuses: ids, accounts: flight.campaign.account.id, })) ); } 2 solved typescript method returning undefined?