Spam calls generally have nothing to do with your phone being hacked. So many companies can sell your contact information, so your phone number is readily available to many parties, including telemarketers and spammers. The main thing to do is to mark those calls as spam and block them. Which phone do you have? One of the great things about Pixels is that they have a powerful built-in spam call screener in the Phone app. Other manufacturers may have something similar (e.g., Samsung has Smart Call: https://www.samsung.com/us/support/answer/ANS10003438/).
Malwarebytes says nothing is on this phone but I've been told that it's been accessed by others is there a way you guys can check this phone, do a netstat or something pls