If you are getting frequent email and phone message for password reset then third party apps or unknown person may have access to your phone number or email address.
Try following methods to prevent frequent password reset mail and sms
1. Change Email Address
Discord allows user to change email address associated with the account.
2. Remove phone number
If you have added phone verification to discord try removing it to check whether the sms and email stops or not
3. Add 2 factor authentication for better security
