The issues is here: https://github.com/0xPolygonHermez/cdk-erigon/blob/7197af7e7f1c4d82de882efbc792d6de56dde4cc/zk/hermez_db/db.go#L1111
func (db *HermezDb) DeleteForkIdBlock(fromBlockNo, toBlockNo uint64) error should delete <forkId, blkNum> records where the key is fork id, but it calls db.deleteFromBucketWithUintKeysRange(FORKID_BLOCK, fromBlockNo, toBlockNo) which uses block number as key.
The logic should be changed such that records with block number in the range [fromBlockNo, toBlockNo] are deleted or updated.