Serious problem with apple music

For the last month there is a problem with apple music and sometimes with apple store as well. In apple music it keeps asking me to sign up (although I am registered and the auto renewal is ON) and when I try to tap sign as individual the screen freezes and no music can be played. When rebooting the iPhone (iPhone 6 i.o.s 8.4.1) everything is back to normal for couple of minutes and than the problem is there again. HELP?