(spewed the first part out before reading the OP, some actual advice at the end.)
I think most problems with taming can be traced to two or more people taming the animal. Either one of them forgot to toggle yield, or they hit at the same time, causing animal to be hit after it gains the taming progress number. Result is animal completely resetting, I think you need to even give it a new clover after you manage to drop the aggro by, for example, entering a house.
This sounds to me that there could be something at fault in the back-end. Possibly the animal doesn't drop the combat relations immediately after yielding, resulting in 0.1 to 1 second window where you can ruin all progress so far (aside from first bringing the animal to your base) by hitting the animal.
Workaround (other than strictly solo-taming) is to tame with two people but only the character that the animal doesn't attack will hit the animal, the one being attacked will only use defensive moves. If DPS isn't sufficient, settle on certain amount of dmg that you deal (most clients track the total number of damage that creature has received) and do double-team damage until you reach that amount, then switch to only one character doing damage.
It's commonly advised to not use melee weapons and this is good advice, but chop with stone axes and Quick barrage with swords might not deal too heavy damage. I should probably explain how I assume the damage will work.

Animal starts losing HP from the right side and as long as you stay in the
Green part, animal keeps fighting without getting ruined. Goal is to hit the
Yellow zone, where animal should yield and add progress to their taming progress counter. However if you dare to reach the completely unmarked and unexplained
Red zone the animal will lose all taming progress and fight you to death.i.e. the problem with dealing too much damage is that you might jump directly from
Green to
Red.
Again, you can reset aggro on animals that went to
Red Zone and leash them back after feeding them a new clover but if this happens consistently, the animal will never tame.