Pelican is regulated by the FCA, they are therefore required to know who their clients are. This may require Pelican asking you to enter address details. In some cases they may also request ID and proof of address documents.
Acceptable ID documents include a scan of your passport or driving licence (scans of the front and back of the document). Proof of address documents include either a bank statement or a utility bill both have to be dated in the last three months.