Got 401 while PUT from Mikrotik RouterOS

I defined two zones, and I wrote my script under Mikrotik RouterOS to update the IP according to my public IP obtained from ISP. it was working beautifully for almost half year. but it suddenly stop working for one of the two zones (x.y.tk) … however the other zone (x.y.cloud) works just fine. also, GET works good for both zones. any hint? here’s my script:
/tool fetch
http-data="{“type”:“A”,“name”:"$MyDomain",“content”:"$MyIP",“ttl”:120,“proxied”:false}"
url=“https://api.cloudflare.com/client/v4/zones/$ZoneID/dns_records/$ID
http-method=put mode=https output=none http-header-field=“X-Auth-Email:$MyEmail,X-Auth-Key:$MyToken,content-type:application/json”