Fatal Error on Install

When I attempt to activate the plugin, I get this:

Parse error: syntax error, unexpected ‘::’ (T_PAAMAYIM_NEKUDOTAYIM) in /home/fgtniphr/book.nftbooking.eu/wp-content/plugins/wp-ulike/includes/action.php on line 98

it seems there is something wrong at line 98 in that file, but I found no other issues in the community about this, so it might be a configuration error on my side?

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