If a customer is unable to access their iTunes or Google Play account to manage Meet Mobile subscriptions they will need to reach out to Apple or Google support

Apple
  • United States - 1-800-275-2273
  • Canada - 1-800-263-3394
  • China - 400-666-8800
  • Australia - (61) 1300-321-456
  • UK - 0800-107-6285
  • Additional Countries - https://support.apple.com/en-us/HT201232
  • Additional Contact Resources - https://www.apple.com/contact/
Google
  • United States  - 855-836-3987
  • Canada - 855-836-3987
  • China - N/A
  • Australia - 1800-093-181
  • UK - 0800-328-6081
  • Additional Countries - https://support.google.com/googleplay/answer/7299936
  • Additional Contact Resources - https://support.google.com/googleplay/answer/7100415?hl=en&ref_topic=6262140