Hi @SenpagaPriya ,
The long url error is due to the standard limit for HTTP requests, which is something that Sentinel Hub cannot work around.
I would suggest rounding the coordinates to 2-3 decimals. Since EPSG:3857 is in meter, it doesn’t mean too much to have the precision to 10^-9 m. Below is the example request:
https://services.sentinel-hub.com/ogc/wms/c139a6b4-4a61-MASKED?SERVICE=WMS&REQUEST=GetMap&FORMAT=image/png&TRANSPARENT=TRUE&VERSION=1.3.0&LAYERS=NDVI&WIDTH=1078&HEIGHT=722&CRS=EPSG:3857&BBOX=3061425.2586273975,5707528.88512473,3064000.231017822,5709253.49557546&TIME=2023-02-13&GEOMETRY=POLYGON%20((3063076.608%205708183.013,3063073.026%205708189.201,3063067.33%205708200.469,3063061.634%205708211.737,3063055.938%205708223.005,3063051.507%205708230.939,3063047.075%205708238.873,3063042.644%205708246.806,3063038.212%205708254.74,3063033.781%205708262.674,3063029.349%205708270.607,3063024.918%205708278.541,3063020.486%205708286.474,3063016.055%205708294.408,3063013.608%205708300.658,3063011.302%205708309.957,3063009.878%205708318.269,3063008.457%205708323.24,3063006.063%205708327.817,3063000.859%205708333.441,3062996.518%205708336.569,3062982.117%205708344.239,3062975.125%205708348.906,3062971.11%205708352.47,3062967.961%205708356.179,3062963.644%205708363.623,3062959.327%205708371.068,3062955.01%205708378.512,3062950.693%205708385.957,3062946.375%205708393.401,3062942.058%205708400.845,3062937.741%205708408.29,3062933.424%205708415.734,3062929.106%205708423.179,3062924.789%205708430.623,3062920.472%205708438.067,3062916.155%205708445.512,3062911.837%205708452.956,3062907.007%205708460.963,3062902.177%205708468.97,3062897.346%205708476.976,3062892.516%205708484.983,3062887.685%205708492.99,3062882.855%205708500.997,3062878.024%205708509.003,3062873.637%205708515.751,3062868.49%205708522.075,3062859.408%205708529.909,3062844.73%205708538.07,3062840.978%205708540.524,3062836.49%205708545.116,3062832.473%205708552.152,3062828.455%205708559.188,3062824.437%205708566.224,3062820.42%205708573.26,3062816.402%205708580.296,3062812.384%205708587.332,3062808.367%205708594.368,3062804.349%205708601.405,3062800.331%205708608.441,3062795.513%205708617.196,3062790.694%205708625.952,3062785.876%205708634.707,3062781.057%205708643.463,3062776.239%205708652.218,3062771.886%205708659.709,3062767.534%205708667.2,3062763.181%205708674.691,3062758.829%205708682.182,3062754.476%205708689.673,3062747.934%205708701.073,3062741.391%205708712.472,3062734.849%205708723.872,3062720.779%205708747.608,3062736.988%205708757.623,3062759.213%205708768.537,3062771.595%205708776.015,3062776.386%205708772.306,3062780.907%205708765.317,3062785.429%205708758.328,3062789.95%205708751.339,3062794.471%205708744.349,3062798.993%205708737.36,3062803.514%205708730.371,3062808.035%205708723.382,3062812.557%205708716.393,3062817.078%205708709.403,3062821.599%205708702.414,3062826.121%205708695.425,3062830.642%205708688.436,3062835.163%205708681.447,3062839.585%205708674.504,3062844.006%205708667.562,3062848.428%205708660.619,3062852.85%205708653.677,3062857.271%205708646.735,3062861.693%205708639.792,3062866.115%205708632.85,3062870.536%205708625.907,3062874.958%205708618.965,3062879.379%205708612.023,3062883.801%205708605.08,3062888.223%205708598.138,3062892.644%205708591.196,3062897.552%205708583.749,3062902.461%205708576.303,3062907.369%205708568.856,3062912.277%205708561.41,3062917.186%205708553.964,3062922.094%205708546.517,3062927.002%205708539.071,3062934.349%205708543.021,3062941.695%205708546.971,3062949.042%205708550.921,3062956.389%205708554.871,3062963.735%205708558.821,3062971.082%205708562.771,3062978.429%205708566.721,3062985.775%205708570.671,3062993.122%205708574.621,3063000.469%205708578.571,3063007.815%205708582.521,3063014.937%205708586.817,3063022.058%205708591.113,3063029.18%205708595.408,3063036.301%205708599.704,3063043.423%205708603.999,3063050.544%205708608.295,3063057.666%205708612.59,3063066.199%205708618.223,3063080.759%205708602.663,3063086.097%205708595.325,3063091.434%205708587.987,3063096.772%205708580.649,3063102.11%205708573.311,3063107.447%205708565.973,3063112.785%205708558.634,3063118.122%205708551.296,3063126.117%205708539.526,3063134.112%205708527.755,3063142.106%205708515.985,3063150.159%205708504.247,3063158.212%205708492.509,3063166.264%205708480.772,3063179.679%205708461.068,3063187.626%205708451.295,3063195.574%205708441.523,3063203.522%205708431.75,3063208.926%205708424.248,3063214.33%205708416.746,3063219.733%205708409.243,3063225.137%205708401.741,3063230.541%205708394.239,3063235.945%205708386.737,3063241.348%205708379.234,3063246.933%205708372.416,3063255.899%205708362.746,3063265.661%205708353.809,3063278.692%205708341.758,3063287.384%205708331.874,3063301.874%205708312.56,3063292.987%205708303.911,3063283.999%205708297.349,3063275.012%205708290.787,3063251.674%205708276.23,3063244.971%205708271.97,3063238.269%205708267.71,3063231.567%205708263.45,3063224.864%205708259.189,3063218.162%205708254.929,3063211.459%205708250.669,3063204.757%205708246.409,3063198.054%205708242.148,3063191.352%205708237.888,3063183.972%205708233.547,3063176.592%205708229.206,3063169.213%205708224.865,3063161.833%205708220.524,3063154.453%205708216.183,3063146.88%205708211.498,3063139.307%205708206.814,3063131.733%205708202.129,3063124.16%205708197.445,3063116.586%205708192.76,3063106.94%205708188.042,3063100.418%205708185.983,3063094.636%205708184.9,3063076.608%205708183.013))
Other alternatives would be simplifying the geometry (having less vertices) or using Process API which takes longer request due to its POST type of requests.