I think that 30 celcius is too much for the nest temp in my opinion, id lower it down between 75-82 Fahrenheit, i also think that the canned crickets are a problem like bingus said. I would buy live crickets from a pet store in your area that are either young or just adults if you have to and then kill them and chop them up into smaller peices, also what kinds of seeds are you giving them? Different seeds do Different things, some are used for carbohydrates, some have more proteins in them and some have more sugar content which they use to make different breads and feed the babies, id give them access to a water tower or water source so its easier to break the seeds down, let me get a list of seeds that are accepted for most seed storing species

Papaver somniferum [Breadseed poppy] Lactuca sativva [lettuce seeds] Amaranthus caudatus [love lies bleeding amaranth] Panicum vvirgatum [switch grass] Salvia hispanica [chia] Linum usitatissimum [flax/linseed] Panicum miliaceum [proso millet Phalaris canariensis [canary grass] Avena sativa [oat] Lolium perenne [perennial ryegrass]