Not a legit loan offer

This company has harassed me for the past few days stating that I have been pre-approved for a loan that I never app**** for. They tried to get me to take a rewards programme (at no cost) as part of the loan application. I declined. Thereafter I was harassed multiple times per day about approving a debicheck mandate for the rewards programme 'to save time later). All this with no information about who pre-approved my loan application and for what amount. Consultants don't seem to call from a call centre (I could hear children, music, car noise in the background on most occassions). Even after blocking their number and refusing their offer, they continue to call from various different numbers