What to do if sort datatable is not working with custom data types?

To resolve the issue of sort datatable, I have a property declared as:

sortedBy = 'contractId';
sortedDirection = 'asc';
Im consuming it in the template as:
    
    
When I hit the sort I utilized the event handler:
onHandleSort(event) {
    const { fieldName: sortedBy, sortDirection } = event.detail;
    const cloneData = [...this.recordToShow];
    cloneData.sort(this.sortBy(sortedBy, sortDirection === 'asc' ? 1 : -1));
    this.recordToShow = cloneData;
    this.sortDirection = sortDirection;
    this.sortedBy = sortedBy;
}
My mistake was on the event handler
    this.sortDirection = sortDirection;
It should be:
    this.sortedDirection = sortDirection;