Unprofessional Property Administrator

I was rather shocked this morning at the treatment of our Client and ourselves by this Property Management Company. We have been managing a Lease for this Client for years now. Solver sends our company the monthly Levy & Utilities invoices so we can pay them on our Clients behalf. At the end of March we settled the full amount for the April levy and utilities used by the Tenant in March only to get an Arrears notice in the 1st week of April advising that we had not in fact paid the full amount as their was an excess amount for the Geyser which was replaced at the beginning of the year. When I queried this with them as the excess for the geyser had not been on the previous invoice, they advised that a mail had been sent out advising that there was an excess to be paid and that the amount would reflect on the STATEMENT and not the INVOICE and that it is very important to check both.I have NEVER ever had to open the statement as everything needing to be paid has always been on the invoice. A statement in my opinion is a history and summary of all invoices and payments. Further to this, the said mail, I never received because they had only sent to the Owner and not to me as they do with the levy accounts.... When questioned as to why, they advised that they are under no obligation to send anything to me and that they had sent to the registered owner and they feel they have done nothing wrong. Why would they send the invoices to me (on instruction of the Owner) each month but not send this mail to me regarding a payment (which I do on behalf of the Owner) of the excess. It makes no sense. The only thing I can deduce is that they forgot to send to me and now trying to pass blame and earn a few extra bucks on penalty fees. If this is not bad enough - the attitude and lack of accountability is unacceptable.