Slow filling toilet cistern

[Pritchy1982]

After flushing it takes around 15 minutes before being able to flush again , is there a step by step guide on how to fix it?

 

[CBW]

Make and model or photo of float valve would help, but if it’s a siamp then curable with a new washer or new valve.

 

[Madrab]

Has it always been slow to fill and is there an isolation valve below the toilet that may be partially closed?

 

[oldbuffer]

As above. If a new(ish) problem, often caused by the rubber diaphragm washer in the inlet valve going hard with age. Change the washer or change the whole valve.

 

[nicam49]

As above, there's a guide on youtube