Proof over payment , what counts more

I would like to share how unprofessional curiocity hotel has been in their administration in terms of booking for accommodation. My experience has been one of a kind, funny enough the initial people I spoke to were understanding and helpful. We had booked for accommodation for the month of October 2018 from the 4th to the 7th, we Made an arrangement with one of the employees (lonna)to pay a portion of our deposit on the 4th of June so as to secure our accommodation for the set dates in October . Payment was made with our reference provided and the only mistake I made was that I did not send proof of payment. Two days later on the 7th of June after payment was made I received an email from Megan(employee at curiocity) saying that they have not received our payment yet arrangement was made with lonna. On the 8th Megan cancels our booking sending an email. I call on the 10th of June to ask if they can check on their side and if payment has refelected using our reference but Megan said we would have to check through our accounts department and then only tell you but for now your booking has been cancelled and there are other people who have booked for the same dates and we have to give them a chance to pay. I asked how could this be possible because all they need to do is check through their accounts if payment was made. I send proof of payment and Megan still says our booking cannot be reinstated negating the fact that we paid on the date as agreed yet the other people whom they are giving a chance to pay have not even paid yet. So all in all Megan was lazy just to go their accounts department to check if payment has been made and I get penalized just for not sending proof of payment in time but payment was made on time and my booking was still cancelled. Other people were given 2 dAys notice to remind them of payment yet I was not.