Samsung The Serif 108 cm E-Manual page 167

Support
Device Care
Support
If the test did not identify any issue, select Settings Support Device Care Self Diagnosis Signal
Information to check the broadcast signal.
Signal Information
Signal strength must be more than 20 dB (more than four bars on the icon) for stable signal reception.
Update now
If the same problem continues, a software update or factory reset may be required.
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