Railjack missions give credits but the credits don´t show on the summary screen. From my latest mission I got about 140k or so but the end mission screen showed like 28.
For me railjack missions used to show how much credits I earned but then some while ago, say about a month or so, it stopped (I figured some missions just didn´t give credits) but then started noticing that my total amount of credits DID change even though the mission didn´t say anything so I started keeping an eye out and just ran another railjack mission, this one was in the void but I´ve ran almost in not all types of mission on most planets and not seen the total credits earned. From this mission I gained about 280k credits (note, this was my first game of the day so was probably actually closer to 140k) but the end screen only showed 28 total credits earned. Before the mission I had 1k something credits (say 1,5k) but I now have 289,988 credits.