This number will call you if someone listed you as a contact for a specific issue (I think student loans of some sort)... Anyway - they are just trying to contact someone else and since your number was given to them as a contact, they are reaching out to you to see if they can get some contact information from you... I think that's all there is to it. They are certainly persistent.

Got a call from this number and I picked up but no one was on the other end

Call to  mobile phone trying to collect a debt for unknown person

Said they are collecting a debt that I do not know

I rec'd a call from this number, in Chicago.......all my bills are paid....I'm retired......and do not have anyone in Chicago........assume its a telemarketer, that somehow got ahold of my mobile #.

Also got a call from this number. Didn't pick up, no voicemail left.