Sewage smell at the Hotel bathroom

I was booked by my employer for four nights at Garden Court Hatfield Pretoria, from 12/10/2015 to 16/10/2015. On the first day I used the bathroom I realised that there was a strong sewage smell coming from the bathroom, but I continued to use the bathroom with the hope that is will subside. On my last day I discovered that the smell was coming from the drain that is installed between the toilet pan and the the shower cubicle. This particular drain was installed to drain any access water that can flood/overflow from the shower/pan/bathtub/wash&amp