I had a console on 4.75 DEX till some time ago. But with the latest plataforms updates from $ony dex under 4.82 couldn't log anymore into PSN without a spoof. It gave you errors at the begining (when they started to change/update things (maybe certs) on their plataform) when you tried to create a new user psn account and later lower dex version couldn't log into PSN, period. Only (rebug) DEX 4.82.x still has access without spoofing, like said already, it's normal, because DEX cames later than CEX, so you can still access the plataform. On DEX, users have to spoof their original IDPS region (85, 87, ... or if using other IDPS the region that IDPS has) with e.g. Webman or they couldn't access PSN (DEX/Debug is 82).
@Xx_Tawwqeerr_xX that screen to update with 3.20 or later is normal when errors (corruption for ex.) do happen on DEX or when you try to install a new HDD or same one (was formatted) but if you are on version 4.81 DEX you know that's the version you need to install or later, if not sometimes you might end up in a instalation loop (easily fixed by formating the hdd).
For what i've read, you used the ps3xploit website to install CFW, swapp to DEX then and for some game you started to get that error. I would delete it's game data (game, updates, dlc), reinstall it again (if it was only for a game) because you might have some corruption on it's files. The rest is normal. To log into PSN you do need a spoof version (SEN ENABLER) or go with 4.82.2 D-REX and update to latest webman and install the new rebug toolbox (if you do have a spoof, you need to uninstall it first if only you decide to update the fw).
Think this will sort you out, by the information you shared.