It must be a widespread octavia if not more models problem as the three octavias i have had have done the same ,pull door handle and it stays out having to give it a nudge to spring back in ,A nuisance when you dont realise and get in and door will not shut into place without reaching round to nudge back in. 

Mine used to do that but always heard it click back as door was closed from drivers seat. I didnt exactly slam it shut. Never caused any issues so never addressed it.