I got a voicemail from the National Research Firm or something like that and it tells me to do a survey of my cell phone use. I do it it tells me to press 1 on my keypad for english and 2 for french but when I press 1 it just keeps on repeating the prompts and the voicemail notifications won't go away on my notifications bar. It will not let me do the survey and it keeps on saying the message was not opened. I sometimes get calls like this so I just want to delete my voicemail. How do I do that? I have a Samsung Galaxy s6.