Originally Posted by ACflyerDE

There is a GBP 132 fare for LHR-LIS-LHR on TP, the fare code is STAP and the booking class is S.

TAP Air Portugal (TP) 38 GBP - - TPROMO
TAP Air Portugal (TP) 42 GBP - - ETAP
TAP Air Portugal (TP) 72 GBP - - UTAP
TAP Air Portugal (TP) 102 GBP - - KTAP
TAP Air Portugal (TP) 132 GBP - - STAP
TAP Air Portugal (TP) 162 GBP - - WTAP
TAP Air Portugal (TP) 192 GBP - - VTAP
TAP Air Portugal (TP) 212 GBP - - JRTTAP
TAP Air Portugal (TP) 240 GBP - - QTAP
TAP Air Portugal (TP) 274 GBP - - HTAP
TAP Air Portugal (TP) 332 GBP - - MTAP
TAP Air Portugal (TP) 412 GBP - - BTAP
TAP Air Portugal (TP) 454 GBP - - ZRTTAP
TAP Air Portugal (TP) 640 GBP - - YSRTAP
TAP Air Portugal (TP) 660 GBP - - DRTTAP
TAP Air Portugal (TP) 740 GBP - - CRTTAP

United.com says "No accrual on S/K/L/T private fares" on TAP, so it appears that you were lucky to get the miles for the outbound flight and you can not expect to get any for the return flight. The funny thing is that you probably would have gotten miles for the ETAP or UTAP fares for less $$$.