The left-hand side of an arithmetic operation must be of type 'any', 'number', 'bigint' or an enum type.ts(2362) Object is possibly 'null'. code example

Example: The left-hand side of an arithmetic operation must be of type 'any', 'number', 'bigint' or an enum type.ts(2362)

new Date("2020-03-15T00:47:38.813Z").valueOf() - new Date("2020-03-15T00:47:24.676Z").valueOf()