2010 Casada with DD15 eng code and regen code

Friday nite an hour east of Amarillo, i get a check engin lite and a lite for high temp on the exhust.
Attempted a rolling regen, no luck, pulled over did a parked regen.
It lasted for about 5 min, then idle back down to low idle, high exhust lite goes off, check enging lite stays on, brough up the code had 16 and 31.
Babied it into Amarillo, no soon as i started rolling High exhust lite comes back on, starts blinking. Called TA petro, and they say we dont change def filters.
So been parked at Amarill Freightliner since.
Not about to take a chance and keep going , and cause damage to the engine.