Garmin Vivofit4 multiple issues

My Vivofit 4 was fairly accurate initiallly,  Now despite recording steps all day, it will give me 0 steps when I sync with my phone.  It undercounts steps by the hunddreds, and the same walk that is 5 miles, has been recorded at anywhere from 4.8 down to 3.5.today.  Seems the most inaccurate on cloudy days, or if I am wearing long sleeves?  Anyone else seeing the same issues?  And if so, is there a solution?  I have not found one yet.