Stream not returning all the data

hello , i am authenticating succsessfull then I send 20 commands to subscribe to 20 different data streams.
this is the final message upon requesting the final symbol :

{"T":"subscription","trades":[],"quotes":[],"bars":["ABG","AAON","AAP","BSJP","BCYC","ARCC","BCV","AAQC","AAQC.U","AQGX","ARCB","ARCKU","AAPL","BSJO","ARC","BSJQ","ARCE","ARCH","BRDS","BCX"],"dailyBars":[],"statuses":[],"lulds":[],"corrections":[],"cancelErrors":[]}

the problem is that im getting only 3-4 messages each minute instead of 20.
any idea what causes this ?