Sending App information problems

I syncronice my device with a FTP server. When I try to send data from the movil App is not possible, “failed to send”. Can you please advice me?
Thank you so much

Is your FTP-provider in Europa? Why I ask: Because of data security laws the complete EU canceled the FTP-services. Only SFTP/secure FTP)-services are allowed. Unfortunately this protocol does not exist in CyberTracker yet.
Holger, Germany (also touched from this)