Use the 'continue from this clip' feature. Next, merge the newly generated segment with the existing one using the 'get whole song' feature.
Or just get creative, use the vocal remover to extend the background sound, cut and paste different parts of it using the good old DAW. By using this method, i managed to make several "full" songs :
Our models support full 2+ mins of coherent generation but generating a couple of verses at a time through continue gives good results you can keep picking the continuations that sound best!
https://app.suno.ai/song/e5c4214b-5851-4ae8-876b-6a99f2ca878... https://app.suno.ai/song/0425b83a-2fa7-4944-9ed8-ba554bd42c3...