point in time restore failing with incompatible

I have a MariaDB 10.6.10 RDS instance running on db.m6g.2xlarge ( 8 vcpu / 32 GB / 20GB SSD), using option group default:mariadb-10-6 and parameter group default.mariadb10.6.

When I try to create a "point in time restore" instance with the same options group, parameter group, db engine version, and instance that is running, the point-in-time restore instance fails to start, with the following status:

incompatible-restore

I've researched a bit on this failure and found this AWS doc (https://aws.amazon.com/premiumsupport/knowledge-center/rds-incompatible-parameters/#:~:text=An%20Amazon%20RDS%20DB%20instance%20in%20the%20incompatible%2Dparameters%20state,version%20or%20DB%20instance%20class.) which discusses matching custom paramters group to default, but I'm already using the ONLY parameter group available, which IS the AWS default for that MariaDB engine (10.6.10).

Any thoughts or insights appreciated.

Thanks