In sandbox mode, several MSISDN are available to ease integration:

MSISDNCode
00000001successful
00000002successful (with delay)
00000003pending (blocked)
00000100failedauthentication_failed
00000200failedunknown_reason
00000202failedfraud_suspicion
00000203failedforbidden_by_provider
00000204failedbad_parameters
00000206failedinvalid_amount
00000207failedcanceled
00000208faileddestination_not_allowed
00000209failedunsupported_currency
00000210failedfraud_suspicion
00000301failedtoo_many_request
00000302failedservice_unavailable
00000303failedinternal_error
00000305failedduplicate_request
00000400failedinvalid_destination

Below is the list of MSISDN available per gateway:

Connector00000001000000020000000300000100000002000000020100000202000002030000020400000206000002070000020800000209000002100000030100000302000003030000030500000400
mm_bf_moov✔️✔️
mm_bj_moov✔️✔️✔️✔️
mm_bj_celtiis✔️✔️✔️
mm_*_wave✔️✔️✔️✔️✔️✔️✔️✔️✔️✔️✔️✔️
mm_ci_moov✔️✔️✔️✔️✔️✔️
mm_ci_mtn✔️✔️✔️✔️✔️✔️✔️
mm_ci_orange✔️✔️✔️✔️✔️✔️
mm_sn_free✔️✔️✔️✔️✔️✔️✔️
mm_sn_orange✔️✔️✔️✔️✔️✔️✔️✔️✔️✔️✔️✔️✔️
mm_tg_moov✔️✔️✔️✔️✔️✔️

*: within the limits of available countries and providers