If you see high bounce rates and your list is moderately new or not consistently used, it may include old or inactive addresses.
But, don't worry, I will help you to verify up to 10.000 for $5 basic gig, check out the extra for more services.
I will check out your list, start from syntax check, remove syntax error, duplicate, invalid domain, bad emails, spam traps (blacklist domain), and mailbox verification. This entire process will run to make sure your hard bounces will disappear from your list,
I will provide you both hygiene email list and the bad one in the end.
What are you waiting for?