Not waterproof tarpaulin.

My wife and I are pensioners and presently live permanently in a Caravan. We have a 2003 Gypsey Caravan so the tent is quite old and has started to leak in rainy weather. I purchased a Covergard 6x4.9 Tarpaulin, from Builders Warehouse in January 2020 for R900. 00, to cover the tent and prevent leaks. The pamphlet with the Tarpaulin states it is waterproof. The rains came and the Tarpaulin leaked all along the joins, thru the stitching, onto the tent and once again the tent leaked. I feel that their statement of the Tarpaulin being waterproof is totally incorrect and I have thrown away R900. 00 which is a lot of money to us pensioners. I trust you will take note of this problem as this to me is false advertising.