USSD Command Codes

*146*00CCNN# - Call
*146*0037251231234# - Call +372 5123 1234

*146*080# - Deactivate Call forwarding
*146*081*00ССNN# - Call forwarding
          *146*081*0079212341234# - Call forwarding to +7 921 234 1234

*146*090# - Deactivate Voicemail
*146*091# - Activate Voicemail
*146*094# - Check number of Voicemail messages
*146*095# - Play Voicemail messages

*146*098 (PIN-code)# - Top up balance with PIN-code
          *146*0981234567890123456#
*146*099# - Balance check

*146*300# - Status check
*146*301# - Show MSISDN
*146*302# - Show Enum (Outgoing number)

*146*710# - Check Skype 800 Calling status
*146*711# - Activate Skype 800 Calling
*146*712# - Deactivate Skype 800 Calling

Calls from Skype:
Activate 711 or 
Deactivate  or *146*712#
 710 or *146*710#

146096# - A call to customer support