ok,
I have resolved my problem ORA-1401 (I have increased the columns with error, after I've export and import again).

But now I get another error:

IMP-00017: following statement failed with ORACLE error 2298:
"ALTER TABLE "ACTS" ENABLE CONSTRAINT "ACTS_SECURITY""
IMP-00003: ORACLE error 2298 encountered
ORA-02298: cannot validate (oradb.ACTS_SECURITY) - parent keys not found
IMP-00017: following statement failed with ORACLE error 2298:
"ALTER TABLE "CLASS" ENABLE CONSTRAINT "CLASS_SECURITY""
IMP-00003: ORACLE error 2298 encountered
ORA-02298: cannot validate (oradb.CLASS_SECURITY) - parent keys not found

these constraints references table groups of user sam.

How can I resolve this problem?
Raf