My printer is stuck in boot logo

My CANON Selphy CP910 used to work for a lot of years without problems. After lying around for > 1 year it doesn't not boot anymore: when I plug in the power cord, I see the boot logo.

I tried turning off and on several times but nothing changed.

Thanks for your help!

crwdns2934089:0crwdne2934089:0 crwdns2934093:0crwdne2934093:0

crwdns2934109:0crwdne2934109:0

crwdns2889612:0crwdne2889612:0 0
crwdns2934285:0crwdne2934285:0