Take advantage of elders who don’t understand technology better

My mother mistakenly paid a few thousands extra for her account and she was asked to send an email with proof of payment and ID which she did , when she called for a follow up she was told they didn’t receive the email. I sent the mail again today and she called to find out if they received it and when can she expect feedback they rudely told her they will get the email Monday cause today it’s Friday and they already knocked of. What kind of service is this?? Is this how are parents are being ****med simple cause they don’t understand technology better? Why would an email reach them on Monday simply cause it was sent Friday???