bad upgrade of my mikrotik router

Good evening I have a mikrotik RB1100 AH router and having no internet connection, I mistakenly updated it with the package of an arm router; and since then it is impossible to access the router; can you help me to downgrade

Hmmmm, usually Mikroitik fails to upgrade with incorrect package types

Have you tried Netinstall to correct?

https://wiki.mikrotik.com/wiki/Manual:Netinstall