I'd double check all the unions for tightness on all the joints. Also I'd use a pressure bleeder such as Easibleed to push fluid through to each corner first then use the two person method below to bleed the brakes.I favour having a clear hose from the nipple to a jar 1/2 full of old fluid and with the nipple closed your assistant pushes the pedal up and down a few times then holds it down then you crack open the nipple and close it again whilst fluid is still flowing.Repeat this a few times on all calipers and start with the caliper furthest away from the master cylinder.
If you still have an issue then it could be a flexible brake line is ballooning under pressure, this can't always be seen from the outside so to test this use a hose clamp on each line in turn to close off then lines one at time . Push the pedal in between and see if you can feel any difference as each line is closed off.
and lastly its possible that there's air trapped in the ABS pump
if you take the car for a short drive and hit the brakes hard as you can to get the pump to trigger and then try re-bleeding again this often works
do you still need help?
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