Dear SIBS Support, 

Since Feb 7th we're getting a HTTP 503 error for around half of our transactions request. Can you tell what's the reason for this API behaviour? Is it a bug on your side or something changed in the API definition? We'd appreciate any info on this matter. 

Example request IDs:

X-Request-ID:d3aeabd17ea64545bd4fbe99bb83736e
X-Request-ID:f73c213260f44ac1ae2258dc8bb54d2d
X-Request-ID:0ec5b2f6bd414e509376d788dbfc4283