The "still-working" exception to taking RMDs only applies to qualified retirement plans like a 401(a), 401(k), 403(b), 457(b) plan or the federal TSP, not to any kind of IRA, so yes, you must take RMDs from your SIMPLE IRA even though you are still working. The requirement to take RMDs from the SIMPLE IRA does not affect your eligibility to contribute to the SIMPLE IRA.
