Can't evolve in Pokemon Mystery Dungeon: Explorers of Sky

I beat the main storyline, and I unlocked Luminous Spring. The first time I went there, they told me I couldn't evolve due to some space related shenanigans, and the second time I went, the narration told me to leave. Is it true? Can I not evolve at all? The Pokemon I wish to evolve are Eevee and Riolu. (Already have Frozen Rock and Sun Ribbon)

Solution 1:

In order for the player or the partner to evolve there, Manaphy needs to tell you about Marine Resort.

After you defeat

Darkrai

do a few more missions and Manaphy will appear. Do anything he tells you to do, then do a few more missions, then he will appear again and tell you about Marine Resort.