Guardian Savings Bank review: Mortgage

I have a re-finance mortgage on my primary residence. I sought Guardian out as my previous residence mortgage was held by them an I had been pleased with the rate, terms and service. There is a 16 day grace period for payments, which I have set automatic withdrawal on the 16th of every month. The teller informed me that I could not make a lump sum principle payment on May 12th until I made the regular monthly payment-because ‘it's after the 1st and the system thinks my payment is late'. Then she said if I had paid the extra to the principal on or before the last day of April-they would have done so. So, against my better judgement-I paid the regular payment then paid extra to the principal. I was not happy with ‘the system thinks' explanation-so I took yet another principal only payment on the 15th and asked ‘since I have already paid this months payment on the 12th-will my automatic payment tomorrow go to the principal? Or will I be a month ahead on my payments?'. The teller had no clue. I was told to call on the 17th and find out. I'm sharing my experience so others will know-the tellers used to be trained and well informed. However, unfortunately this is no longer the case. My last mortgage experience with them, not only did I not have silly problems, attitudes and lack of service-but I was even encouraged by the tellers to keep making extra principal payments whenever possible-every time I went there! Such a disappointing difference.