Assuming you are not running HDX, this might be due to plugin ADC. Start by setting MIX window to show Delay Compensation and check the numbers(especially the bottom of the 3 as that is the total Delay Compensation). If the numbers are more than 32(give or take), that will create a problem when you enter record, because the delay compensation is disabled on any track in record(which would put your new audio ahead of other audio that is delayed due to delay compensation).
Best practice for tracking(non-HDX) is to set the buffer to 64(assuming 44.1 or 48K) and disable any plugins that show more than 10 samples of latency. In the case of a large session with plugins that you really NEED to hear during an overdub, I would bounce a mix>Import into the session>nudge into perfect alignment>Make all tracks inactive(except the new bounced mix) and record overdubs to that. Once finished, mute the 2-mix and re-activate all tracks. LLM can SOMETIMES help, but it often either just doesn't work, or won't quite do what you want
