I have a ‘22 Rize RX with Bafang Ultra mid drive. Rode 3000 miles last year with no problems. Got tuneup at LBS before winter. When I took it out first time this spring, everything works fine EXCEPT…. Throttle only works intermittently. As in, throttle engages for about a second, cuts out, engages again, cuts out, etc. Pedal assist fine at all levels and speeds. Have tried plugging/unplugging throttle connectors with no luck. Any ideas on what’s causing or what to try to fix before I take back to shop? Thanks in advance for any help!