Security Federal Credit Union

I am not a member of this credit union, but I found out that if you ARE a member not in good standing (ie late credit card payment), Security Credit Union will sic a collection company on your FAMILY. I have received numerous calls from numbers that do not take calls back (such as 700−000−0000). They have also been calling my parents incessantly, using different numbers so they can’t be blocked. I do not answer these calls, but they leave a voicemail asking for my relative (one even used MY name) and to have them contact the credit union at such and such number. I have called the credit union twice to have them take my number off the list. Hopefully the calls will stop soon. Ultimately, what am I supposed to do about my relatives bills?!