IP reset failure

Hello there,

I'm having really strange issue, because when I reset my ip using command prompt with this command: netsh int ip reset, it comes back as a access denied or failed (I went into regedit and changed permissions in folder 26 to full). When few days ago I put in netsh int ipv4 reset it worked, but when I put ipv6 reset then it wouldn't work. Few days later (now) its the other way around, ipv4 reset doesn't work and ipv6 reset works. ????? My provider gives me dynamic IP, however everytime I reset PC, or wake up and boot up my PC its always the same IP that I see in command prompt using: Ipconfig command. Even now when I reset ipv6 in command prompt and I restart my PC its still the same ipv6 after restart as it was before restart. I called provider today and they told me that ip would change only if I had my pc turned off for a longer period of times (24 hours), but then later in the same call she told me that it would reset at specific time, for example 10:48, even if it wasn't shut down for 24 hours LOL.... I called them once some time ago when they changed my IP from static to dynamic, they said that IP should change very often. What is going on guys?