I wrote Back then we won often, which I believe to be also correct
It is accepted. Please do use the report function (My answer should be accepted) next time, do not just write into the discussion.
What is wrong with "We would frequently/often win back then"? And why is the continuous tense used in the proposed solution? Shouldn't simple tense be used with words like often, frequently, seldom, always etc.?
"We would win frequently back then." is already accepted. I do not know whether your word order is the same.
I do not think that the continuous tense with frequently is wrong. If you do, please tell us why, show some reference or some other reason.
Incase you didn't just make a typo there I wanted to point out he said 'then' and you said 'than'. 'Than' should be incorrect.
This is a typo/spelling mistake I do quite frequently. Unfortunately.
Can we say ""Tehdy jsme vyhráli často."?
Would it have the same meaning?
No, it is strange. Často/often means it was repeated so you need the imperfective verb. You can say "Tehdy jsme vyhráli." for "We won back then.".
I see. Thank you!