Make your banker love you - correct [make - causative verb; it is followed by a short infinitive verb - love-] ; banker is in the accusative case; it is not the subject of the sentence.
'Make' as a causative verb expresses the idea that the person requires another person to do something.
Subject + Make + Person + Base Form of Verb
Peter made her do her homework.
The teacher made / makes the students stay after class.
Your banker loves you - correct [ banker - subject; loves - verb 3rd person singular]