How to take lid off a dual flush cistern?

[rolling]

Thanks everybody. It did unscrew - ended up jamming a screwdriver in beside the big button to get enough leverage.

Took filler mechanism to pieces and cleaned out, but still takes 20+ minutes to fill despite good H2O supply. Think the little insert may be torn. Can you get spares (like washers) or is it a new filler?

 

[leonardsmusic]

'Rolling', I am sure you have fixed it by now, but for others interested, you can obtain a new washer from B&Q that fits this type of inlet valve. As noted in previous posts elsewhere, a slow filling cistern is quite often caused by a torn washer in the inlet valve inside the large round plastic (nylon?) nut. Thanks for the help everyone, I've just sorted my one out, too!

 

[Mrtychrs]

I have a lid mechanism like the photo from Rolling. Remove the 2 buttons and then whole mechanism with prongs turns anticlockwise. Bit stiff but unscrews eventually.