stains in middle of print

Some more stains on my print, caused by the head touching the paper. the paper roll is very very curly.

yesterday i cut sheets from the roll and covered the paper with foam board and books for extra weight.

That did not do much ( one night )

What is a good way to uncurl a paper roll?

Epson pro 9880 and Hahnemuhle Fine Art Baryta Satin 44" roll

 

Kind Regards,

 

Luc