ur car saga fl, so, battery already surface pass at least 2 years i guess (my fl ady 3+ years change batter last year)
looks like your battery kong ady. jumps car should ok already.
u jumps start with what car? if jump start with kancil car sure cannot jump start liao. should use 300amp lorry/truck jumper cable.
can try disconnecting & reconnecting the battery connector first.
try to use other battery first to confirm.
if cannot can call auto assist if you have one OR call bawah pokok mechanic if available.
if around keramat, can help you but later in evening la.

will transfer you to others to answer your questions.
iinm triton use N70 battery ( i just hack into triton thread  ).. saga N60. dunno saga can support.
maybe try other jumper cable as the cable rosaked perhaps?
btw what brand battery u use?
iinm ur battery last 1 year ady. considered lucky if can last more than that.

or maybe immobilizer rosaked perhaps?
try using other spare keys?

Plonk jump start kabel, leave triton injin running for 5 minits dulu, don't touch the GaGa until 5 minit. Then try setat lagi, by right 1 kik sudah hidup.

Another thing is, when u say selow & kenot setat, does it sound like "hick hick hick heeeeee" or "wuek... Kek... Kek... Kek...." Lidat? If hick hick hick no kek kek kek sound, no need setat liao, taiming belt sudah putus simpan duet oberhol lar. If kek... Kek... Kek selowly, means not enuf powah to setat. If oni hear tek tek tek sound, mungkin setater relay koyak or bat3 totally flat, ur setater totally relying on jumper kabel liao, hence not even got enuf powah to push setater solenoid out, macamane mau hear the injin kek kek kek sound?

Plotong GaGa/Perdangna V6  setater is dual layer solenoid geh, won't rosak so easily. Usually pipu(bad magician) like to kondem GaGa setater rosak is bcoz after the bugger tukak relay den cheat u say sudah tukak setater. Tibai relay baru RM25 nanti he cas u RM400 tukak setater sebenarnyer talak tukak, mana boley tak senang "rosak"?