dsp4life, temp protection is only a problem if it's affecting your vape experience; i.e. if you can feel the vape cutting in and out, or if it's too cool for your liking. If it vapes fine, then "temp protection" is just the mod letting you know that it's throttling back the wattage to maintain the temperature you want, which is exactly what it's supposed to do.
That said, you've definitely got a problem somewhere, as you should definitely be getting good vapor production at those temps - I can take mine all the way down to 175C and still get loads of vapor.
I would doublecheck all your connections - those screws on the subtank mini RBA don't always trap the wire well, and the 510 pin is press fit so it can mess up a TC experience as well. Tighten your screws down and make sure the RBA is screwed into the deck well, then try it again.
If that still doesn't fix it, I'd try completely redoing the build; again, having built on the subtank mini RBA about 200 times now, it's those screws to trap the wire I would instantly suspect is causing the problem, and if tightening the screws doesn't fix it, it will be easier to do a complete rebuild since you can leave the legs long and use those to really pull the wire underneath the screw head until you're 100% sure you've got the legs solidly trapped.
I assume you're running the most recent firmware? If not, do that as well since they've adjusted the SS algorithm a few times now.
My build:
Tank –
SKU 3990801 (Black Crius clone)
Mod - Evic vtc mini
Single or Dual or Beyond Coil/s – dual vertical, 316L SS
TC – 210 C
Watts - 50
Coil Inner Diameter – 2.5mm
AWG - 28
Wraps – 6 1/2
Final Resistance – 0.37
Verdict – rewicking this build is a bit of a faff - have to put small vertical bits of cotton into the wick ring and between the posts. Then trim to size a piece of the firmer outside layer of a piece of muji/koh-gen-do, and wrap tightly all the way round the deck, making sure it’s touching the outside surface of your coils; adding a drop or two of juice as you go helps keep everything in place. Trim the top edges back if necessary, make sure the coils are directly centred over the airholes and you can see straight down through them (no cotton covering the tops of the coils), then carefully screw the chimney on. It looks a great deal like many of the factory multi-coil subtank heads when you’re done, except with less cotton. All of this is, however, a faff that’s *completely* worth it to me... no leaking, good airflow, can chain vape with no dry hits, and the flavour is off the charts. Amazingly, I easily get two weeks out of my wicking with this build, whereas with a horizontal one I’m lucky to get 4 days.