Trial of Auricular Vagus Nerve Stimulation in Painful Covid Long

Inclusion Criteria: Subjects aged 18 to 80 with prolonged post-Covid-19 pain defined by 3 criteria according to the Haute Autorité de Santé : * Symptomatic initial episode of Covid-19 is confirmed by at least one criterion among: PCR SARS-CoV-2 +, antigenic test SARS-CoV-2 +, Serology SARS-CoV-2 +, prolonged anosmia / ageusia of sudden onset , chest scanner * Presence of at least one of the initial symptoms, beyond 4 weeks following the onset of the acute phase of the disease * Initial and prolonged symptoms not explained by another diagnosis with no known link to Covid-19 * With intact and uninjured skin at the level of the cymba concha of the left ear * Signature of informed consent * Pain of intensity\> or equal to 40 mm / 100mmm on the Visual Analogue Scale (VAS) over the last 7 days before inclusion, analgesic treatment stable for at least 2 weeks * Must be able to comply with protocol requirements * Beneficiary of a social security scheme or entitled Exclusion Criteria: * Having a hearing aid device with a left cochlear implant * Having a major hearing loss * Having an unsuitable ear canal * Use of other electrically active medical devices (TENS for chronic pain, pacemaker) * Taking treatment with strong opioids, corticosteroids or nonsteroidal anti-inflammatory drugs systemically (oral, subcutaneous, intravenous, intramuscular, transdermal). * With cognitive disorders that do not allow answering questionnaires and /or setting up the device * Known history of cardiac arrhythmias, atrioventricular block\> 1st degree, conduction disorders * Symptomatic orthostatic hypotension or history of recurrent vagal syncope * History of vagotomy * severe asthma * Pregnant, breastfeeding or having a desire to become pregnant