Here’s a list of their toll-free phone numbers in various countries: mastercard.fi/…/global-services-phone-numbers.pdf

And the content of that file, in case that they might remove that link: Mastercard Global Service™ Local Toll-Free Telephone Numbers American Samoa 1-1-800-307-7309 Japan 00531-11-3886 Anguilla 1-800-307-7309 Korea, Republic of 0079-811-887-0823 Antigua and Barbuda 1-800-307-7309 Liechtenstein 0800-89-7092 Argentina 0800-555-0507 Luxembourg 800-2-4533 Australia 1800-120-113 Malaysia 1-800-804594 Austria 0800-07-06-138 Mexico 001-800-307-7309 Bahamas 1-800-307-7309 Monaco 0-800-90-1387 Bahrain 8000-0087 Montserrat 1-800-307-7309 Barbados 1-800-307-7309 Netherlands 0800-022-5821 Belgium 0800-1-5096 New Zealand 800-441-671 Bermuda 1-800-307-7309 Norway 800-12697 Bolivia 800-10-0172 Panama 001-800-307-7309 Bonaire 001-800-307-7309 Peru 0800-77-476 Brazil 0800-891-3294 Philippines 1-800-1-111-0061 Cambodia 800-881-001 then 877-288-3891* Poland 0-0800-111-1211 Canada 1-800-307-7309 Portugal 800-8-11-272 Cayman Islands 1-800-307-7309 Puerto Rico 1-800-307-7309 Chile 1230-020-2012 The Russia 8-800-555-02-69 China 10-800-110-7309** Saba 1-800-307-7309 China 2 10-800-711-7309*** St. Eustatius 1-800-307-7309 Colombia 01-800-912-1303 St. Maarten 1-800-307-7309 Costa Rica 0-800-011-0184 St. Kitts-Nevis 1-800-307-7309 Curacao 001-800-307-7309 Saipan (N. Marianas) 1-800-307-7309 Cyprus 080-90569 San Marino 800-870-866 Czech Republic 800-142-494 Saudi Arabia 800-844-9457 Denmark 8001-6098 Singapore 800-1100-113 Dominica 1-800-307-7309 South Africa 0800-990418 Dominican Republic 1-800-307-7309 Spain 900-822-756 Finland 08001-156234 Sweden 020-791-324 France 0-800-90-1387 Switzerland 0800-897-092 Germany 0800-071-3542 Taiwan 00801-10-3400 Greece 00-800-11-887-0303 Thailand 001-800-11-887-0663 Grenada 1-800-307-7309 Trinidad and Tobago 1-800-307-7309 Guam 1-800-307-7309 Turkey 00-800-13-887-0903 Guatemala 1-800-999-1480 Turks and Caicos 01-800-307-7309 Hong Kong 800-966677 United Arab Emirates 800-0444-3895 Hungary 06800-12517 United Kingdom 0800-96-4767 India 000-800-100-1087 United States 1-800-307-7309 Indonesia 001803-1-887-0623 Vatican City State 800-870-866 Ireland 1-800-55-7378 Venezuela 0800-1-002902 Israel 180-941-8873 Vietnam 120-11576 Italy 800-870-866 Virgin Islands, 1-800-307-7309 Jamaica 0800-307-7309 Virgin Islands, U.S. 1-800-307-7309 Last Updated 31 January 2019