How to delete ALL activities/records etc inside the Garmin connect web interface?

Hi,

i have buyed a used fenix 5s plus from a friend and after the start all activities/records etc are imported from the watch to my accound.

but thats are not my activities, thats the activities etc from my friend.

How i can delete them ALL.

Atm i have no own activities at my account, so it is ok if ALL datas are lost.

thx

Steve