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as already written: we don´t know what this is. In your schematic we see a non standard symbol with pin names and pin numbers, but no idea what it does. Other capacitors have no value at all.
Unsure what "220 2000B" means.
So how do you think we can give a good answer? All we can do is guess...
Give useful information, device part names, a more complete schematic, context ... and we can help you.
Looks like digital RS422 isolator, e.g. ADM2682. Working voltage between input and output side can be 1 kV and more. The capacitor in the schematic snippet has apparently 2000 V specification.
We call it an Y-capacitor, purpose can be reduction of fast voltage transients that may affect the digital data as well as reduction of high frequent noise generated by the isolator itself. Analog Devices family of isoPower devices (integrated dc/dc converter) is known to cause heavy EMI in the several 100 MHz range and easyily causes failure of EMC requirements. If the intended isolation function is still achieved with a relative large Y capacitor - depends.