Duo issue with plat+

I was ranked plat 3 last season but ended up not getting season rewards because I got banned once. I'm now trying to que up with my friends who were plat/diamond last season for the placements but league is telling me ineligible "duo partner". I'm able to que up with friends who are gold/silver but not plat+. Does this have something to do with league not recognizing that I was actually plat because my rewards and border were taken away?