I think somebody has misunderstood a comment made by Zelenskyy at the International Summit on the Support of Ukraine, held this February just passed. Zelenskyy said:

We remember that Russia has violated the ceasefire more than 25 times since 2014.

Zelenskyy is talking about the ceasefire which formed part of the Minsk agreements. Representatives from both Ukraine and Russia signed these agreements, with the final protocol's first point being:

1. To ensure an immediate bilateral ceasefire.

This is the ceasefire agreement which Russia has violated. That is to say, there haven't been 20 separate ceasefire agreements, there was one which Zelenskyy told the Summit Russia had violated more than 25 times.