Toto Dual flush - not filling

I have had a Toto Aquia One-Piece Toilet, Dual Flush toilet (1.6GPF & 0.9GPF Model MS654114MF) for a couple of years and all of a sudden it stopped filling. Any advice on what this might be. Sediment ? other common causes. Need advice on how to fix.

Thanks all

www.terrylove.com/korky

Servicing Instructions for working on the fill valve on the bottom of the page.

Korky 528T Replacement TOTO Toilet Fill Valve - Fits G-Max and Power Gravity Toilets -Easy to Install -Made in USA

If after servicing the valve it doesn't solve the problem, turn off the water to the toilet, disconnect the supply hose from the valve, and holding the hose over a bucket or something turn the water and see if any comes out the hose in a good flow. If not, then you may have a defective FloodStop hose (that is supposed to cut off for excessive flow). Replace it with a normal hose and you should be fine.

Korky video on servicing the valve (Korky makes the green-capped fill valve that Toto uses in the Aquia):