Go to the SolusVM control panel
https://solusvm.prometeus.net/
Login using the credentials you received with the account ready message when your VPS was provisioned
Click on the "manage" button of the vps you are going to reinstall
Click on the "reinstall" button under the General tab
Select one of the templates available and click on reinstall. Warning! All existing data will be wiped out, so please backup your files before doing a reinstall.