When importing data from CSV, Field defined as 'double?' got error "must be of type 'number?', got 'string'"

[xyzzyxyzzy0077]

Schema

{
  name: 'products',
  properties: {
    category: 'string',
    type: 'string?',
    standard: 'string?',
    bonnet_type: 'string?',
    top_flange_standard: 'string?',
    option_2: 'string?',
    option_3: 'string?',
    actuation: 'string?',
    actuation_option_1: 'string?',
    actuation_option_2: 'string?',
    pn_pressure_rating: 'string?',
    size: 'int?',
    f2f_standard: 'string?',
    f2f: 'double?',
    c2s: 'double?',
    c2b: 'double?',
    fig_no: 'string?',
    p_no: 'string?',
    supplier: 'string?',
    features: 'string?',
    inlet_standard: 'string?',
    inlet_connection: 'string?',
    inlet_thread_or_solder_pipe_size: 'string?',
    inlet_flange_diameter: 'int?',
    inlet_flange_pcd: 'int?',
    inlet_flange_no_holes: 'int?',
    inlet_diameter_holes_or_thread_size: 'string?',
    outlet_standard: 'string?',
    outlet_connection: 'string?',
    outlet_thread_type: 'string?',
    outlet_flange_diameter: 'int?',
    outlet_flange_pcd: 'int?',
    outlet_flange_no_holes: 'int?',
    outlet_diameter_holes_or_thread_size: 'string?',
    top_standard: 'string?',
    top_flange_diameter: 'int?',
    top_flange_pcd: 'int?',
    top_flange_no_holes: 'int?',
    top_diameter_holes: 'int?',
    top_bolt_or_stud_size: 'string?',
    body_material: 'string?',
    body_material_grade: 'string?',
    trim_material: 'string?',
    trim_material_grade: 'string?',
    seal_material: 'string?'
  }
}

Data
LANDING ANGLE,RIGHT ANGLE,,,,,,,,,,25,,,65.00,85.00,Fig JIS7334H,145325,ECONOSTO,,JIS 10K,FLANGED,,,,,,,,,,,,,,,,,,,BRONZE,,BRASS,,

But got

NOTE: There are 10,000+ records in the csv file

[bmunkholm]

This product is now deprecated. The replacement "Studio" can also import CSV files. Please see if that's still causing the same issue.
Thanks!

[xyzzyxyzzy0077]

Oops, sorry I didn't mention that this actually came from Realm Studio.

I've managed to upload all of the data by adding a '@' symbol (such a primitive yet only way to converse type) in the beginning of every record, then manually delete them in the cloud.

Now I am looking for a way, in Realm js, to change the types of the schema's properties in a sync realm, but with no luck. Do you have any suggestions? (I sure will post this question on StackOverflow, but would like to ask here anyway)