I've experienced before and currently now in M81 where after the first round of FA signings, I try to adjust my current offer and I get bonus cannot make up more than 75% of contract. Mostly when I try to extend from a 4-5 yr contract to a 5-6 without touching the sliders. I can exit and withdraw the contract and then extend a new one without the same restrictions with more bonus. .

I've had this same issue, for some reason the bonus doesn't adjust properly in this situation.

I think its calculation is off when you adjust the existing offer. If I move both sliders a bit then go back to max it readjusts and submits.