One of the important ingredients to success is being Consistent-
I use to have a driver from NY that drove for us that always seemed grumpy but with our customers he could find a smile and always did his job- I called him Mr. Happy.
( We may have a few of those drivers on now too )
I always goy along fine with him and tried to always fine that bridge with all drivers and employees and agents- we do not always have to slap our leg with laughter with every conversation as long as the job gets done. I did not mind Mr. Happy because he was consistent- I always knew what I was going to get. Unlike some people that put on a act for you and are happy one day and mad the next- I rather know what I am going to get then worry about what person was going to show up on any given day.
Do not worry about being buds with everyone - just do your job.
We are all different and for whatever reason some people you will gravitate to and others you may not- as they said in the Godfather- Don't take it personal - it's business.
Just be consistent- treat people with respect - and do your job.