push button

Hi all, The button on our toilet has essentially locked up so we're having to push the plunger manually. Are these fairly easy to replace? I'm not sure of the brand so any help identifying a suitable replacement part/s would be appreciated (and any fitting advice). Thanks in advance!

I have the Fluidmaster PRO550UK fitted to a cistern in the house. https://www.amazon.co.uk/Fluidmaster-PRO550UK-Front-Mounted-Flush/dp/B0060X5Q0A/ref=pd_lpo_vtph_60_bs_t_1?_encoding=UTF8&refRID=X9T0EAWVS9C7588BV1R7&th=1 Generally it works exceptionally well, but occasionally when the large...