The MAX10 and Cyclone10 families are both pretty new and should be in production for likely the remainder of this decade.
But welcome to 2022. Most semiconductors are severely supply constrained. Most distributors are out of stock.
Virtually all production is going to big customers with pre-negotiated supply contracts.
Off the shelf distributors are usually low man on the totem pole when it goes to allocation.
Consensus seems to be at sometime in 2023 or possibly 2024 things should get back to normal.
Most distributors are not even accepting back orders at this point as they don't expect to see any parts this year.