
977 So.2d 701 (2008)
Henry RIGGINS, Appellant,
v.
STATE of Florida, Appellee.
No. 4D08-440.
District Court of Appeal of Florida, Fourth District.
March 19, 2008.
Rehearing Denied April 21, 2008.
Henry Riggins, Perry, pro se.
No appearance required for appellee.
PER CURIAM.
The trial court struck Riggins' rule 3.800(a) motion as moot, reasoning that he had already served the challenged ten-year habitual felony offender (HFO) sentence, which was imposed in 1991. It is not at all clear that the motion was moot; Riggins stated in his motion that the challenged sentence was imposed consecutive to a twenty-year HFO sentence imposed in another case. Prior related cases in this court reflect that the twenty-year sentence was imposed earlier in 1991 for an unrelated 1990 case.
Nevertheless, we affirm because some of the grounds could have been dismissed as successive, in that they were raised in prior unsuccessful motions, and none of the grounds is cognizable in a rule 3.800(a) motion. Thus, the grounds that could not be dismissed as successive should have been denied. See Thompson v. State, 945 So.2d 627 (Fla. 4th DCA 2006) (affirming dismissal, where trial court, instead, should have denied the rule 3.800(a) motion); Sweeney v. State, 944 So.2d 474 (Fla. 4th DCA 2006) (same).
Affirmed.
STONE, POLEN and GROSS, JJ, concur.
