Not working Doorbell

Help! My ring doorbell hasn’t worked for a few months I have tried to reconnect and start a fresh and it has worked for 20mins. Then a delivery guy pressed the bell and it worked but since then it’s not working… no flashing white light it’s just flashing blue! The batteries are fully charged and both when used is the same. I am paying £49 a year for what??? Can anyone help? Thank you C x