Netzwerk Telekom Service interview questions

They invited in the office for an interview, informed me that will provide me a feedback in time period around two weeks, they never provided me any feedback (pasted or no). After two and half months, i sent them an email and they called me to arrange a new interview for a different position this time, (without to provide feedback regarding the first position -interview). During the online interview they never showed up and when i contact them, they answered me, that they forgot to inform me that position was occopied and they cancelled my interview. Very unprofessional behavior from their side.