So I know one can't collect a power more than twice as to avoid farming, but I thought that after ascending this would not apply anymore... I just ascended and i can't collect Peloponnesian War ML. Thank you

Even after ascending, you can't collect any powers you've already collected twice.

Interesting... It's my second ascend and I was adamant I had collected more than twice some powers but Ok. This does present new and interesting challenges

Some powers you already collected got removed and some new powers got added. Thats why it might feel that you collected some powers more than once, but its actually 2 different powers.