Awful smell in bathroom need someone to fix it

Hi,we have an apartment that we rent out and last week there was a sewage smell in the bathroom,looked on talk Quesada website and it recommended Unblockarod,they came out and said it was coming from the shower and it was stagnant water,they couldn’t do anything,could you please recommend a plumber who can sort this out for me.Its never been a problem before but recently they were doing the drains at the side of our apartment block.Please could you help.Thank you

Nobody has replied!!

Here’s what I’d recommend. After cleaning your bathroom, pour beach down the drain and leave. I don’t think the plumbing in bathrooms is anything like in the U.K. You could put bungs into bath and wash hand basin to stop odours from coming up from the drains.
Cheers,
Rosemary.

I think their assessment is possibly wrong, the waste traps on showers in apartments are very shallow, hence they don't hold much water, so when it starts getting hotter the water in the waste traps evaporates, which in turn allows the smell from the sewer pipe system to pass through.

The Spanish tend to use a little bit of olive oil, it sits on top of the water in the trap and stops it evaporating, whilst ever the shower is being used daily you shouldn't get any smell, only when not used for a couple of weeks.

I agree. Pour bleach down the plugholes and the put plugs in. We leave a plunger over the shower drain and this seems to help when we're not using the shower.

However we did have a problem with sewage smells from our toilet - which was something to do with the plumbing - so if you eliminate the sink and shower and you still get the smell, you'll probably need a plumber.

Thank you all for your help.I really appreciate it