The blockage might be further down the line or in the external manhole. Maintenance Tips to Prevent Future Clogs
Start by removing the drain cover. Manually pull out any visible hair or debris near the surface. If you can see a "hair monster" just below the grate, use a wire hanger or a "drain snake" to pull it out first. The bicarbonate soda works best on the sludge that remains. 2. The Boiling Water Flush how to unblock a shower drain with bicarbonate soda