Stream not connect, but historical agg fine

Hi Everyone,
I was using polygon streaming, it was fine, but just the past few days, it stopped working. The historical agg from polygon works. The code did not change, sometimes after quite a whiel, it prints error message like. “unknown channel A.TACO (you may need to specify the right data_stream)”. Other times, it just hangs there, nothing happens. Tried to print sth right at the beginning of the async loop, nothing printed. When I try to run it from jupyter notebook, it says sth like the eventloop is already running, but nothing is happening.
I contacted polygon, and was told that they do not recognize the error message. Can anyone suggest a solution to this issue, Thanks a bunch!
def run_ws(conn, channels):
try:
conn.run(channels)
except Exception as e:
print(e)
conn.close()
run_ws(conn, channels)