Option A) engage "cut" in amp block (under bass parameter in 1st pg of amp block)
Option B) in cab block, slowly turn up "low cut" until the flabbiness goes away (don't look at the number- just listen); also, make sure it is set to 6db/oct.
Option C) setup a filter block at the beginning of the signal chain, that cuts some low end (though this is only necessary if your other pedals in front of the amp are also sensitive to excessive bass
Option D) in amp block, turn up "definition" parameter until the bass sounds right. If that adds to much top end, you can go back and turn down treble or presence in a variety of ways, in either the amp block or cab block.
Option E) if you are using a Compressor block in front, turn off "Auto," turn "Look Ahead" up to about .500, Attack 15-35 ms, "Filter" at or above 100Hz ("Studio Comp" only)
Option F) add a Sm57 mic in the cab block
Option G) pick a different cab
Option H) in cab block, disable "Proximity effect"
Option I) if using delay or reverb blocks, go to EQ page of that block and turn the low cut (high-pass filter) up to at least 120
Option J) if you have the "Boost" engaged within the amp block,....disengage it. Being on the front end of the amp, it can add significantly more bass (for better or worse). Use a T808 pedal in front of the amp block instead.