Hey there 4teacher,
Thanks for reaching out to Apple Support Communities. We understand you’re receiving some phishing calls and messages without the option to decline them. We’ll be happy to help.
One thing that may help would be to turn on Silence Unknown Callers and follow the rest of the steps in this link:
Detect and block spam phone calls
Then follow the steps in article to filter and block any messages you get as well:
Filter and block messages on iPhone
Also, follow the steps under “If you get a suspicious phone call or voicemail” from this link as well:
Recognize and avoid phishing messages, phony support calls, and other scams
We hope this helps.
Take care.