luceos true, but not necessarily the case. It's possible that the IP address itself is a target from a range or subnet, or has even been hit by mistake. Nonetheless, a DDoS of that magnitude can be bought in the dark web for less than your weekly coffee cost. Remember that a DDoS is virtually all cases it not from one lone IP. It's an army of unknowing and unwilling zombies that have been created by previous compromise and are under influence of a C&C (command and control).
All the originators of the attack do is provide a list of targets, them flip a switch to start it. What's more likely is that the IP you are using has been previously attributed to an institution that had been a target before, and they've changed their IP range in order to curb the attacks. You've landed up with that IP and now are using the price.
Check DNS blacklists first and see if you're IP is listed. Failing that, it's a dark web search to see how you've been targeted, or change your IP which is always going to be quicker and cleaner.
