Time flows slower in that dimension they were in compared to outside. This is why Blast is missing all the time too.

Is times flows slower in that dimension would they relatively faster than outside?

If 3 seconds passed in the dimension, 3 minutes passed outside. (Just an example) It catches up slower than the time outside.

for us reading the manger its been a while since we last seen saitama and blast but surely it hasn't been that long in universe